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josmiceli answered: 9695 problems
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�t�e�s�t/723450: I hate you guys!!!!!!!!!!!!!?
I need help but you guys told me wrong!!!!!!!!!!!!!!!?
Why did you do this??????????????
Never going to trust you again!!!!!!!!
1 solutions

Answer 443178 by josmiceli(9697) About Me  on 2013-03-07 21:26:00 (Show Source):
You can put this solution on YOUR website!
If someone purposely misled you, that
would really suck! If it was just a dumb mistake,
welcome to the real world. I've totally blown
a few problems myself. I know which ones to
leave alone. Sorry for the crappy experience.


Mixture_Word_Problems/723297: How much water should be added to 40 liters of a 75% acid solution to dilute it to 60%? I know the current solution has 30 liters of acid (.75x40), but I'm having difficulty with the equation for the dilution.
1 solutions

Answer 443117 by josmiceli(9697) About Me  on 2013-03-07 17:17:15 (Show Source):
You can put this solution on YOUR website!
The liters of acid never changes
+.75%2A40+=+30+ liters of acid
Let +w+ = liters of water to be added
+30+%2F+%28+40+%2B+w+%29+=+.6+
+30+=+.6%2A%28+40+%2B+w+%29+
+30+=+24+%2B+.6w+
+.6w+=+6+
+w+=+10+
10 liters of water must be added


�t�e�s�t/723288: a king hires a crew of 30 workers, who can build a castle wall in 60 days. However, 10 days after the wall was started, the king decided that the wall must be finished in a total of 40 days. How many additional workers must be hired if all the workers work with the same constant rate?
1 solutions

Answer 443113 by josmiceli(9697) About Me  on 2013-03-07 17:12:14 (Show Source):
You can put this solution on YOUR website!
Let +R+ = the rate at which a single worker works
Add their rates of working to get their rate
working together
+30R+=+1%2F60+
( the +1%2F60+ means 1 wall / 60 days )
+R+=+1%2F1800+
---------------
The 30 workers work for 10 days.
Let +x+ = the fraction of the wall they finish
+30R+=+x%2F10+
+1%2F60+=+x%2F10+
+x+=+1%2F6+
So, 5/6 of the wall must be finished in +40+-+10+=+30+ days
Let +n+ = the number of additional workers needed to
finish the wall in 30 more days
+%28+30+%2B+n+%29%2AR+=+%28+5%2F6+%29+%2F+30+
+30R+%2B+n%2AR+=+5%2F180+
+n%2AR+=+5%2F180+-+1%2F60+
and, since +R+=+1%2F1800+
+n%2A%28+1%2F1800+%29+=+50+%2F+1800+-+30%2F1800+
Multiply both sides by +1800+
+n+=+20+
20 workers must be added to finish in 40 days
check:
can +30+%2B+20+=+50+ workers do 5/6 of the wall
in 30 days?
+50R+=+%28+5%2F6+%29+%2F+30+
+50%2A180%2AR+=+5+
+R+=+5+%2F+9000+
+R+=+1%2F1800+
OK


Equations/723289: Please help solve this problem.I come up with x= 4 and y= -1...Not too sure what to do after that or if that is the right answer.
Solve using multiplication principle first and then add:
3x-4y=16
5x+6y=14
1 solutions

Answer 443098 by josmiceli(9697) About Me  on 2013-03-07 16:41:46 (Show Source):
You can put this solution on YOUR website!
Check your answers by plugging them
back into the equations:
( 4,-1 )
+3x+-+4y+=+16+
+3%2A4+-+4%2A%28-1%29+=+16+
+12+%2B+4+=+16+
+16+=+16+
OK
+5x%2B6y=14+
+5%2A4%2B6%2A%28-1%29=14+
+20+-+6+=+14+
+14+=+14+
Your answers are correct


Rational-functions/723286: When you add, subtract, multiply or divide are there any special rules to consider when dealing with integers?
1 solutions

Answer 443094 by josmiceli(9697) About Me  on 2013-03-07 16:35:03 (Show Source):
You can put this solution on YOUR website!
Yes.
You can multiply by +0+,
but you can't divide by +0+
-------------
When multiplying, ( - ) x ( - ) = ( + )
( - ) x ( + ) = ( - )
----------------
( - ) / ( - ) = ( + )
( + ) / (- ) = ( -)
( - ) / ( + ) = ( - )
All the rest are pretty simple


Word_Problems_With_Coins/723188: claire purchases a new washing machine on clearance sale for 259. if the clearance price was 65%off the original price what was the original price of the washing machine?
1 solutions

Answer 443081 by josmiceli(9697) About Me  on 2013-03-07 14:18:32 (Show Source):
You can put this solution on YOUR website!
Let +p+ = the original price
given:
+p+-+.65p+=+259+
+.35p+=+259+
+p+=+259+%2F+.35+
+p+=+740+
The original price was $740


Exponents/723227: A population of 75 foxes in a wildlife preserve quadruples in size every 15 yr. The function
y= 75 * 4^x , where x is the number of 15 yr periods, models the population growth. How many foxes will there be after 45 years?

1 solutions

Answer 443080 by josmiceli(9697) About Me  on 2013-03-07 14:13:50 (Show Source):
You can put this solution on YOUR website!
+45%2F15+=+3+
So there are 3 of the 15 year periods in 45 yrs
+y+=+75%2A4%5E3+
+y+=+75%2A64+
+y+=+4800+
In 45 yrs, there will be 4800 foxes


Travel_Word_Problems/723222: The Jones family drove to Disneyland at 50 m.p.h and returned on the same route at 40 m.p.h. Find the distance to Disneyland if the total driving time was 7.2 hours.
1 solutions

Answer 443079 by josmiceli(9697) About Me  on 2013-03-07 14:08:12 (Show Source):
You can put this solution on YOUR website!
Let +d+ = distance in miles to Disneyland
Let +t+ = time in hrs to get there
+7.2+-+t+ = time in hrs to get back
--------------
Equation for going:
(1) +d+=+50t+
Equation for coming back:
(2) +d+=+40%2A%28+7.2+-+t+%29+
By substitution:
+50t+=+40%2A%28+7.2+-+t+%29+
+50t+=+288+-+40t+
+90t+=+288+
+t+=+288%2F90+
+t+=+3.2+
-------------
(1) +d+=+50t+
(1) +d+=+50%2A3.2+
(1) +d+=+160+
and
(2) +d+=+40%2A%28+7.2+-+t+%29+
(2) +d+=+40%2A%28+7.2+-+3.2+%29+
(2) +d+=+40%2A4+
(2) +d+=+160+
The distance to Disneyland is 160 mi


Travel_Word_Problems/723178: george can install new wiring for a computer in 3 hours. it takes pete 4 hours. how long will ot take if they work together
1 solutions

Answer 443077 by josmiceli(9697) About Me  on 2013-03-07 13:56:25 (Show Source):
You can put this solution on YOUR website!
Add their rates of working
( 1 job ) / ( 3 hrs ) + ( 1 job ) / ( 4 hrs ) = ( 1 job ) / ( t hrs )
+1%2F3+%2B+1%2F4+=+1%2Ft+
Multiply both sides by +12t+
+4t+%2B+3t+=+12+
+7t+=+12+
+t+=+12%2F7+
+t+=+1.7143+ hrs
+.7143%2A60+=+42.86+
Working together it will take them 1 hr and 43 min


Travel_Word_Problems/723216: a freight train leaves a station and travels north at 60 mph. two hours later, a passenger train leaves on a parallel track and travels north at 100 mph. how long will it take the passenger train to overtake the frieght train? how far from the station will they meet
1 solutions

Answer 443075 by josmiceli(9697) About Me  on 2013-03-07 13:46:35 (Show Source):
You can put this solution on YOUR website!
In 2 hrs, the freight train gets a head start of
+60%2A2+=+120+ mi
Let +d+ = the distance the passenger train has to
travel to catch the freight train
-----------------
Start a stopwatch when the passenger train leaves
Let +t+ = the time on the stopwatch when they meet
------------------
Equation for freight train:
+d+-+120+=+60t+
Equation for passenger train:
+d+=+100t+
------------
By substitution:
+100t+-+120+=+60t+
+40t+=+120+
+t+=+3+ hrs
and
+d+=+100t+
+d+=+100%2A3+
+d+=+300+ mi
They will meet 300 mi from the station
check:
+d+-+120+=+60t+
+300+-+120+=+60%2A3+
+180+=+180+
OK


Mixture_Word_Problems/723201: It takes Ralph 6 hours to paint a fence. Lisa can do the same job in 10 hours. If Ralph paints alone for 30 minutes before Lisa begins helping, how long must they work together to finish painting the fence? Give your answer to three decimal places.




1 solutions

Answer 443070 by josmiceli(9697) About Me  on 2013-03-07 13:36:47 (Show Source):
You can put this solution on YOUR website!
The question to ask is: "What fraction of the job does
Ralph get done in a 1/2 hour ?"
------------------
Multiply Ralph's rate of painting times 1/2 hr
( 1 fence / 6 hrs ) x ( 1/2 ) = 1/12
So Ralph finishes 1/12 of the fence in 1/2 hr
---------------
There is 11/12 of the fence left to paint
Add their rates of painting to get their rate
painting 11/12 of the fence
+1%2F6+%2B+1%2F10+=+%2811%2F12%29+%2F+t+
Multiply both sides by +12t+
+2t+%2B+1.2t+=+11+
+3.2t+=+11+
+t+=+11%2F3.2+
+t+=+3.438+
They must work together for 3.438 hrs to finish


Travel_Word_Problems/723156: A plane travels 100 mph in still air. It travels 240 miles into the wind and
240 miles with the wind in a total time of 5 hours. Find the wind speed.
1 solutions

Answer 443065 by josmiceli(9697) About Me  on 2013-03-07 13:21:50 (Show Source):
You can put this solution on YOUR website!
Let +w+ = the wind speed in mi/hr
+100+%2B+w+ = the plane's speed going with the wind in mi/hr
+100+-+w+ = the plane's speed going against the wind in mi/hr
Let +t+ = plane's time going against the wind in hrs
+5+-+t+ = planes time going with the wind in hrs
----------------
Equation going against the wind:
(1) +240+=+%28+100+-+w+%29%2At+
Equation going with the wind:
(2) +240+=+%28+100+%2B+w+%29%2A%28+5+-+t+%29+
-----------------------------
(2) +240+=+500+%2B+5w+-+100t+-+w%2At+
(2) +w%2At+%2B+100t+-+5w+=+260+
(2) +t%2A%28+100+%2B+w+%29+=+260+%2B+5w+
and,
(1) +240+=+%28+100+-+w+%29%2At+
(1) +t+=+240+%2F+%28+100+-+w+%29+
Substitute this result into (2)
(2) ++%28240+%2F+%28+100+-+w+%29%29+%2A%28+100+%2B+w+%29+=+260+%2B+5w+
(2) +240%2A%28+100+%2B+w+%29+=+%28+260+%2B+5w+%29%2A%28+100+-+w+%29+
(2) +24000+%2B+240w+=+26000+%2B+500w+-+260w+-+5w%5E2+
(2) +5w%5E2+=+2000+
(2) +w%5E2+=+400+
(2) +w+=+20+
The wind speed is 20 mi/hr
------------------------
check answer:
(1) +240+=+%28+100+-+w+%29%2At+
(1) +240+=+%28+100+-+20+%29%2At+
(1) +240+=+80t+
(1) +t+=+3+ hrs
and
(2) +240+=+%28+100+%2B+w+%29%2A%28+5+-+t+%29+
(2) +240+=+%28+100+%2B+20+%29%2A%28+5+-+t+%29+
(2) +240+%2F+120+=+5+-+t+
(2) +2+=+5+-+t+
(2) +t+=+3+ hrs
OK




�t�e�s�t/723179: I have a question. For i= the square root of -1, if 3i(2+5i) = x+6i, then x =
A. -15 B. 5 C. 5 D. 15 E. 27
1 solutions

Answer 443060 by josmiceli(9697) About Me  on 2013-03-07 12:56:34 (Show Source):
You can put this solution on YOUR website!
+3i%2A%28+2+%2B+5i+%29+=+x+%2B+6i+
Use the definitions:
+i+=+sqrt%28-1%29+
+i%5E2+=+-1+
+6i+%2B+15i%5E2+=+x+%2B+6i+
+x+=+15i%5E2+
+x+=+15%2A%28-1%29+
A. +x+=+-15+


Rate-of-work-word-problems/723180: If 4 workers can pack 16 parcels in 8 hours then how many could 8 workers pack in 4 hours?
1 solutions

Answer 443058 by josmiceli(9697) About Me  on 2013-03-07 12:52:11 (Show Source):
You can put this solution on YOUR website!
Twice as many worker can pack twice as many
parcels in the same amount of time, so
8 workers can pack 32 parcels in 8 hours
In half of that time, the same number of workers
could pack half as many parcels, so
8 workers can pack 16 parcels in 4 hours


logarithm/722987: how long will it take for the populations of a certain country to double if its annual growth rate is 6.2%?
1 solutions

Answer 442975 by josmiceli(9697) About Me  on 2013-03-06 22:00:42 (Show Source):
You can put this solution on YOUR website!
Let P[n] = population after +n+ years
Let +P+ = the starting population
+r+ = rate of growth of population
------------
+P%5Bn%5D+=+P%2A%28+1+%2B+r+%29%5En+
given:
+2P+=+P%2A%28+1+%2B+.062+%29%5En+
+2+=++1.062%5En+
+log%282%29+=+n%2Alog%281.062%29+
+n+=+log%282%29+%2F+log%281.062%29+
+n+=+.30103+%2F+.02612+
+n+=+11.525+ yrs
+.525%2A12+=+6.3+
+.3%2A30+=+9+
It will take 11 years 6 months and 9 days



Rate-of-work-word-problems/722406: aron, Brenda, Charlie, and Danita are house painters. The team of Aaron, Brenda, and Charlie can paint my house in 3 days; if Aaron and Danita work as a pair it takes 6 days; the pair of Charlie and Danita takes 8 days, and the team of Brenda, Charlie, and Danit can finish in 5 days. How long would it take the whole 4-person crew to paint my house?
1 solutions

Answer 442761 by josmiceli(9697) About Me  on 2013-03-06 00:16:19 (Show Source):
You can put this solution on YOUR website!
Let +r%5Ba%5D+ = Aaron's rate of painting in houses/day
Let +r%5Bb%5D+ = Brenda's rate of painting in houses/day
Let +r%5Bc%5D+ = Charlie's rate of painting in houses/day
Let +r%5Bd%5D+ = Danita's rate of painting in houses/day
----------------------------------------------
Add rates to get the rate working together
(1) +r%5Ba%5D+%2B+r%5Bb%5D+%2B+r%5Bc%5D+=+1%2F3+
(2) +r%5Ba%5D+%2B+r%5Bd%5D+=+1%2F6+
(3) +r%5Bc%5D+%2B+r%5Bd%5D+=+1%2F8+
(4) +r%5Bb%5D+%2B+r%5Bc%5D+%2B+r%5Bd%5D+=+1%2F5+
---------------------------
This is 4 equations and 4 unknowns, so it should be solvable
Subtract (4) from (1)
(1) +r%5Ba%5D+%2B+r%5Bb%5D+%2B+r%5Bc%5D+=+1%2F3+
(4) +-r%5Bd%5D+-+r%5Bb%5D+-+r%5Bc%5D+=+-1%2F5+
(4) +r%5Ba%5D+-+r%5Bd%5D+=+5%2F15+-+3%2F15+
(4) +r%5Ba%5D+-+r%5Bd%5D+=+2%2F15+
--------------------
Add this result to (2)
(2) +r%5Ba%5D+%2B+r%5Bd%5D+=+1%2F6+
(4) +r%5Ba%5D+-+r%5Bd%5D+=+2%2F15+
+2r%5Ba%5D+=+5%2F30+%2B+4%2F30+
+2r%5Ba%5D+=+1%2F30+
+r%5Ba%5D+=+1%2F60+
---------------
and, since
(2) +r%5Ba%5D+%2B+r%5Bd%5D+=+1%2F6+
(2) +1%2F60+%2B+r%5Bd%5D+=+1%2F6+
(2) +r%5Bd%5D+=+10%2F60+-+1%2F60+
(2) +r%5Bd%5D+=+9%2F60+
(2) +r%5Bd%5D+=+3%2F20+
You can finish- have to go


Miscellaneous_Word_Problems/722401: Bob Hope was born 2 years after Clark Gable and 2 years before Henry Fonda. In 1951, after all three had their birthdays, the sum of their ages was 144. In what years were they born?
My work:
2-x+2+x+x=144
x=140
I can't figure out how to make the equation or the to find the years each were born.
1 solutions

Answer 442736 by josmiceli(9697) About Me  on 2013-03-05 20:36:45 (Show Source):
You can put this solution on YOUR website!
Let +x+ = Clark Gable's age in 1951
+x+-+2+ = Bob Hope's age in 1951
+x+-+4+ = Henry Fonda's age in 1951
given:
+x+%2B+x+-+2+%2B+x+-+4+=+144+
+3x+-+6+=+144+
+3x+=+150+
+x+=+50+
+x+-+2+=+48+
+x+-+4+=+46+
-------------
Clark Gable was born in +1951+-+50+ = 1901
Bob Hope's was born in +1951+-+48+ = 1903
Henry Fonda was born in +1951+-+46+ = 1905


Percentage-and-ratio-word-problems/722370: the base material for a certain roadbed is 80% crushed rock when measured by weight. How many tons of this material must be mixed with another material containing 30% rock to make 150 tons of material that is 40% crushed rock?
1 solutions

Answer 442732 by josmiceli(9697) About Me  on 2013-03-05 20:17:16 (Show Source):
You can put this solution on YOUR website!
Let +a+ = tons of 80% crushed rock needed
Let +b+ = tons of 30% crushed rock needed
given:
(1) +a+%2B+b+=+150+
(2) +%28+.8a+%2B+.3b+%29+%2F+150+=+.4+
---------------------------
(2) +.8a+%2B+.3b+=+.4%2A150+
(2) +.8a+%2B+.3b+=+60+
(2) +8a+%2B+3b+=+600+
--------------------
Multiply both sides of (1) by 3
and subtract (1) from (2)
(2) +8a+%2B+3b+=+600+
(1) +-3a+-+3b+=+-450+
+5a+=+150+
+a+=+30+
and, since
(1) +a+%2B+b+=+150+
(1) +30+%2B+b+=+150+
(1) +b+=+120+
30 tons of 80% crushed rock are needed
120 tons of 30% crushed rock are needed
check:
(2) +%28+.8a+%2B+.3b+%29+%2F+150+=+.4+
(2) +%28+.8%2A30+%2B+.3%2A120+%29+%2F+150+=+.4+
(2) +%28+24+%2B+36+%29+%2F+150+=+.4+
(2) +60+=+.4%2A150+
(2) +60+=+60+
OK


Miscellaneous_Word_Problems/722321: A wide screen TV is priced at $3000 was on sale for 30 percent off. When the TV didn't sale,an additional 10 percent of the sale price was taken off the sale price.What sort of equation do I need to write to solve this?
1 solutions

Answer 442714 by josmiceli(9697) About Me  on 2013-03-05 18:11:20 (Show Source):
You can put this solution on YOUR website!
You can say that +x+ is the original price
( $3,000 in this case )
Also say that +p+ is the price after whatever discounts
are applied
After 1st discount:
+p+=+x+-+.3x+
+p+=+.7x+
-----------
After 2nd discount:
+p+=+.7x+-+.1%2A%28+.7x+%29+
+p+=+.7x+-+.07x+
+p+=+.63x+
--------------
Now just say +x+=+3000+ and
solve for +p+, the current price


Word_Problems_With_Coins/722275: Given nine nickels and four pennies, find how many different sums of money can be formed using one or more coins.
1 solutions

Answer 442709 by josmiceli(9697) About Me  on 2013-03-05 16:50:05 (Show Source):
You can put this solution on YOUR website!
Using just the nickels, there are 9 possible sums
( 5, 10, 15, 20, 25, 30, 35, 40, 45 )
Using just pennies, there are 4 possible sums
( 1, 2, 3, 4 )
+9+%2B+4+=+13+ so far
---------------------
Each of the 4 possible sums using pennies can
be combined with any one of 9 possible sums
using nickels.
+4%2A9+=+36+ possible sums
------------
+13+%2B+36+=+49+
There are 49 possible sums


Rate-of-work-word-problems/722152: If 3 persons can do 3 times of a particular work in 3 days then 7 persons can do 7 times of that work in
1 solutions

Answer 442673 by josmiceli(9697) About Me  on 2013-03-05 13:34:38 (Show Source):
You can put this solution on YOUR website!
3 persons can do 3 jobs in 3 days
1/3 of the work will take 1/3 of the time, so
3 persons can do 1 job in 1 day
It will take 1 person 3 times as long, so
1 person can do 1 job in 3 days
7 persons can do 7 times the work in the same time, so
7 persons can do 7 jobs in 3 days
-----------------------------


Travel_Word_Problems/722171: If an airplane travels 525 miles per hour, how fast does it travel in feet per minute?
1 solutions

Answer 442672 by josmiceli(9697) About Me  on 2013-03-05 13:25:13 (Show Source):
You can put this solution on YOUR website!
In terms of units,
( miles / hour ) x ( feet / mile ) x ( hours / minutes ) = feet / minute
+525%2A%285280%2F1%29%2A%281%2F60%29+=+46200+
525 mi/hr = 46,200 feet/min


Complex_Numbers/722194: how do i solve (5-4i)^2
1 solutions

Answer 442667 by josmiceli(9697) About Me  on 2013-03-05 13:11:49 (Show Source):


Linear_Equations_And_Systems_Word_Problems/722190: Cashews sell for $5.00 a pound and peanuts sell for $2.00 a pound. How many pounds of each would you use to make 25 pounds of a mixure that sells for $92.oo?
1 solutions

Answer 442666 by josmiceli(9697) About Me  on 2013-03-05 13:07:04 (Show Source):
You can put this solution on YOUR website!
Let +c+ = pounds of cashews needed
Let +p+ = pounds of peanuts needed
given:
(1) +c+%2B+p+=+25+
(2) +5c+%2B+2p+=+92+
-------------------
Multiply both sides of (1) by 2
and subtract (1) from (2)
(2) +5c+%2B+2p+=+92+
(1) +-2c+-+2p+=+-50+
+3c+=+42+
+c+=+14+
and, since
(1) +c+%2B+p+=+25+
(1) +14+%2B+p+=+25+
(1) +p+=+11+
14 pounds of cashews are needed
11 pounds of peanuts are needed
check:
(2) +5c+%2B+2p+=+92+
(2) +5%2A14+%2B+2%2A11+=+92+
(2) +70+%2B+22+=+92+
(2) +92+=+92+
OK


Mixture_Word_Problems/722182: You need to make 1.5 liters of a 30% salt solution. How much salt do you need? Be sure to include proper units
1 solutions

Answer 442665 by josmiceli(9697) About Me  on 2013-03-05 12:57:31 (Show Source):
You can put this solution on YOUR website!
Let +s+ = liters of salt needed
+s+=+.3%2A1.5+
+s+=+.45+
You need .45 liters of salt


Rational-functions/722184: So, the question in my textbook reads:
"Determine whether the given value of x is a non-permissible value for the rational expression."
a) "(3x + 9)/[(x-5)(x+6)]
I did the work for the denominator and found that the Non-permissible values for 'x' are "5 and -6."
The numerator factors to 3(x+3), however I am not sure if I have to do anything with the numerator. 5/0 is considered undefined, but is 0/5? please help. thank you so much.
1 solutions

Answer 442664 by josmiceli(9697) About Me  on 2013-03-05 12:50:06 (Show Source):
You can put this solution on YOUR website!
+0%2F5+=+0+ is permissible
You have the correct answers


Human-and-algebraic-language/722167: A room contains 96 chairs. The number of chairs per row is four more than the number of rows. Find the number of rows and the number of chairs per row.
1 solutions

Answer 442662 by josmiceli(9697) About Me  on 2013-03-05 12:47:38 (Show Source):
You can put this solution on YOUR website!
Let +r+ = the number of rows
+r+%2B+4+ = the number of chairs /row
+r%2A%28+r+%2B+4+%29+=+96+
+r%5E2+%2B+4r+=+96+
Complete the square
+r%5E2+%2B+4r+%2B+%284%2F2%29%5E2+=+96+%2B+%284%2F2%29%5E2+
+r%5E2+%2B+4r+%2B+4+=+96+%2B+4+
+r%5E2+%2B+4r+%2B+4+=+100+
+%28+r+%2B+2+%29%5E2+=+10%5E2+
take the square root of both sides
+r+%2B+2+=+10+
+r+=+8+
+r+%2B+4+=+12+
The number of rows is 8
The number of chairs /row is 12
Check:
+8+%2A+12+=+96+
OK


Money_Word_Problems/722040: Jeane worked 45 hours one week and earned a $380.00 paycheck. She earns time and a half (1.5 times her regular hourly wage) for the number of hours she works in excess of 40. What is Jeane's regular hourly wage?
1 solutions

Answer 442593 by josmiceli(9697) About Me  on 2013-03-04 23:38:45 (Show Source):
You can put this solution on YOUR website!
Let +x+ = her regular hourly wage
+1.5x+ = her overtime hourly wage
given:
+40x+%2B+5%2A%281.5x%29++=+380+
+40x+%2B+7.5x+=+380+
+47.5x+=+380+
+x+=+8+
Her hourly wage is $8/hr


Polynomials-and-rational-expressions/721854: I cant seem to figure out how x squared+x-12 works
1 solutions

Answer 442536 by josmiceli(9697) About Me  on 2013-03-04 18:10:07 (Show Source):
You can put this solution on YOUR website!
(1) It's a function. You can call it f(x), or
a function of x.
That means that there is 1 and only 1 value of f(x)
for each value of x.
-------------------
If there were 2 possible values of f(x) for a certain x,
then it would be disqualified as a function.
------------------------------------
(2) It's a 2nd degree equation, also called a parabola
Here's the plot:
+graph%28+400%2C+400%2C+-5%2C+5%2C+-16%2C+5%2C+x%5E2+%2B+x+-+12+%29+
---------------
You can see that there are 2 x-crossings, called roots. That is a feature
of 2nd degree equations- 2 real roots. If there were no
x-crossings at all, then there would still be 2 roots,
but they would be imaginary.
---------------------------
Hope this helps



Linear_Equations_And_Systems_Word_Problems/721832: A vendor learned that, by pricing caramel apples at $1.75 sales will reach 57 caramel apples per day. Raising the price to $2.75 will cause that sale to fall to 13 caramel apples per day. Let y be the number of caramel apples the vendor sells at x dollars each. Create a linear equation that models the number of caramel apples sold per day when the price is x dollars each. Then determine how many apples will sell per day if the cost is lowered to $1.50.
1 solutions

Answer 442531 by josmiceli(9697) About Me  on 2013-03-04 17:56:42 (Show Source):
You can put this solution on YOUR website!
The given points are:
( x1,y1 ) = ( 1.75, 57 )
( x2,y2 ) = ( 2.75, 13 )
-------------------
Use the point-slope formula
+%28+y+-+13+%29+%2F+%28+x+-+2.75+%29+=+%28+57+-+13+%29+%2F+%28++1.75+-+2.75+%29+
+%28+y+-+13+%29+%2F+%28+x+-+2.75+%29+=+44+%2F+%28-1%29+
+y+-+13+=+-44%2A%28+x+-+2.75+%29+
+y+=+-44x+%2B+121+%2B+13+
+y+=+-44x+%2B+134+ answer
If the cost is $1.50,
+y+=+-44%2A1.5+%2B+134+
+y+=+-66+%2B+134+
+y+=+68+
68 apples/day will sell if the price is $1.50/apple
---------------
check:
Does the line go through ( 1.75, 57 ) ?
+y+=+-44x+%2B+134+
+57+=+-44%2A1.75+%2B+134+
+57+=+-77+%2B+134+
+57+=+57+
OK
You can check the other point


Miscellaneous_Word_Problems/721721: Don drew a scale drawing of a county park. The scale he used was 7 inches = 1 yard. What is the scale factor of the drawing?
1 solutions

Answer 442475 by josmiceli(9697) About Me  on 2013-03-04 12:54:34 (Show Source):
You can put this solution on YOUR website!
In units:
( yards )x( ft/yard )x( in/ft ) = in
+1%2A%283%2F1%29%2A%2812%2F1%29+
+3%2A12+=+36+ in
The scale factor is +7%2F36+