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Travel_Word_Problems/270285: how much time does it take the cheetah to travel 500 meters, if its average speed is 70 meters per second?
1 solutions

Answer 198030 by rfer(12644) About Me  on 2010-02-16 12:48:28 (Show Source):
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500/70=7.14 sec


Complex_Numbers/270282: what is 3h-5h+11=17 and what is 7g+14-5g=-8 and what is 4=0.4(3d-5) abd what is 2/3g+1/2g=14
1 solutions

Answer 198029 by rfer(12644) About Me  on 2010-02-16 12:47:11 (Show Source):
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3h-5h+11=17
combine
-2h=6
divide by -2
h=-3
--------------------
7g+14-5g=-8
2g=-22
g=-11
-------------------
4=.4(3d-5)
4=1.2d-2
6=1.2d
d=5
-----------------
2/3g+1/2g=14
4/6g+3/6g=14
7/6g=14
g=14*6/7
g=84/7
g=12


percentage/269927: Circle below represents a whole, or 1. Use subtraction to determine the unknown part of the circle. The unknown part of the circle is?
1/4 6/16

1 solutions

Answer 197831 by rfer(12644) About Me  on 2010-02-15 19:53:56 (Show Source):
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4/16+6/16=10/16
16/16-10/16=6/16=3/8


test/269989: Mr.Beck lost 1 pound the first week of a diet, lost 3 pounds the second week, and gained 2 pounds the third week. What was his net gain or loss?
1 solutions

Answer 197828 by rfer(12644) About Me  on 2010-02-15 19:48:24 (Show Source):


Miscellaneous_Word_Problems/269953: What is the value of "score" in "four score and seven years ago?"
1 solutions

Answer 197827 by rfer(12644) About Me  on 2010-02-15 19:47:41 (Show Source):
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a score is a set of 20
4 score=80 yrs


Probability-and-statistics/269987: Seven girls' names and four boys' names are placed in a hat. One name is drawned and replaced. A second name is drawn. What is the probability that both names drawn are girls' names?
1 solutions

Answer 197826 by rfer(12644) About Me  on 2010-02-15 19:44:40 (Show Source):
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7/11*7/11=49/121


Miscellaneous_Word_Problems/269956: What percent would be received on a score of 27/89 rounded to the nearest hundredths place?
1 solutions

Answer 197825 by rfer(12644) About Me  on 2010-02-15 19:42:11 (Show Source):
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27/89=.30=30%


Circles/269958: A circle has an area of 25 pie sqaure centimeters. What is the length of its diameter?
If someone could answer this question for me, that would be great! Thanks.
1 solutions

Answer 197823 by rfer(12644) About Me  on 2010-02-15 19:39:32 (Show Source):
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A=pir^2
A=3.14*25
r=5 cm
d=10 cm


Coordinate-system/269961: what is the x-intercept of the graph 8x+4y=16
1 solutions

Answer 197822 by rfer(12644) About Me  on 2010-02-15 19:36:27 (Show Source):
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8x+4y=16
8x+4*0=16
x=2
(2,0)


Miscellaneous_Word_Problems/269967: A church steeple casts a shadow 115 ft. long and at the same time a 9.0 ft post casts a shadow 7.0 ft long. How high is the steeple? round to the nearest unit.
1 solutions

Answer 197821 by rfer(12644) About Me  on 2010-02-15 19:34:17 (Show Source):
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x/115=9/7
7x=1035
x=148 ft


Trigonometry-basics/269983: what is the formula for solving "what is the diagonal of a rectangle?"
1 solutions

Answer 197820 by rfer(12644) About Me  on 2010-02-15 19:30:05 (Show Source):


Pythagorean-theorem/269981: Find the length of the leg of this right triangle. Give an approximation to 3 decimal places.
the triangles sides are 35, 30, and a


a. 8.062 c. 46.098
b. 17.748 d. 18.028

1 solutions

Answer 197819 by rfer(12644) About Me  on 2010-02-15 19:29:32 (Show Source):
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35^2+30^2=c^2
1225+900=2125
c=46.098
C)
It could be answer D)18.028
It says leg, so the way it is writen it is hard to tell
if they are looking for the diagonal or one of the legs.


Geometry_Word_Problems/269979: "a movie theater charges 5.00 for an adult ticket and 2.00 for a childs ticket. One saturday the theater sold 785 ticket for 3280. How many childs tickets were sold for the movie that saturday?"
1 solutions

Answer 197817 by rfer(12644) About Me  on 2010-02-15 19:23:44 (Show Source):
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a+c=785 a=785-c
5a+2c=3280
--------------
5(785-c)+2c=3280
3925-5c+2c=3280
-3c=-645
c=215 children
a=570 adults


Money_Word_Problems/269974: Jason spent 8 hours sanding the boat deck. He charges $6.00/h. His expenses were $4.00/h to rent the sander and $0.10/h for electricity. What was his net profit?
1 solutions

Answer 197815 by rfer(12644) About Me  on 2010-02-15 19:19:44 (Show Source):
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(6*8)-(4*8+.1*8)=
48-32.8=$15.20 net


Equations/269975: Mark scored 15 points more than Gary on a math quiz. Their combined scores are 183 points. How many points did Gary earn?
1 solutions

Answer 197813 by rfer(12644) About Me  on 2010-02-15 19:15:54 (Show Source):
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x+x+15=183
2x=168
x=84
x+15=99


Graphs/269976: In the problem 2y-8=x what is the next step to put it in slope intercept form? do you add the 8 to its self then add it to the x? then would it be 2y=x+8?
1 solutions

Answer 197812 by rfer(12644) About Me  on 2010-02-15 19:14:22 (Show Source):
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2y-8=x
2y=x+8
now divide by 2
y=1/2x+4
----------
slope m=1/2
y int b=(0,4)


Percentage-and-ratio-word-problems/269600: Complete the table below in which interest rates are given as decimals.
* Principal X annual interest rate = one year's interest
61.
Principal: $12,000
X Annual interest rate: 0.1025
= one year's interest: ?
63.
Principal: $2500
X Annual interest rate: ?
= one year's interest: $275
65.
Principal: ?
X Annual interest rate: 0.09
= one year's interest: $180
PLEASE I NEED HELP.
I DO NOT UNDERSTAND THIS QUESTION
if can may you do it step by step please?
thank you very much
1 solutions

Answer 197611 by rfer(12644) About Me  on 2010-02-14 21:24:33 (Show Source):
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61)
12000*.1025=$1230
63)
275/2500=0.11=11%
65)
180/.09=$2000


Percentage-and-ratio-word-problems/269572: In a nation of 221 million people, the urban population is 2.25 times the rural population. Find the rural and urban populations.
1 solutions

Answer 197609 by rfer(12644) About Me  on 2010-02-14 21:17:03 (Show Source):
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221/3.25=68 mill rural
68*2,25=153 mill urban


Geometry_Word_Problems/269638: i need to find the area and perimeter of my room wich is 10x9 feet and take it to inches

1 solutions

Answer 197607 by rfer(12644) About Me  on 2010-02-14 21:08:53 (Show Source):
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10*12=120 in
9*12=108 in
P=2*120+2*108
P= 240+216
P=456 in
---------------
A=120*108
A=12,960 sq in


expressions/269180: What is the evaluation the following expression when x = 4.2.
34.5x

1 solutions

Answer 197394 by rfer(12644) About Me  on 2010-02-13 20:37:17 (Show Source):
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34.5*4.2
144.9


Unit_Conversion_Word_Problems/269278: A 2500 g bag of sugar was on sale for $ 0.95. How much would you have to pay for 30 kg of sugar?
Thank you! : )
1 solutions

Answer 197393 by rfer(12644) About Me  on 2010-02-13 20:33:39 (Show Source):
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30/2.5*.95=$11.40


Angles/269284: the smallest angle in a triangle is 1/5 as large as the largest angle. the third angle is twice the smallest angle. Find the three angles.
1 solutions

Answer 197392 by rfer(12644) About Me  on 2010-02-13 20:30:38 (Show Source):
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x+.2x+2(.2x)=180
x+.2x+.4x=180
1.6x=180
x=112.5 degrees
.2x=22.5 degrees
2(.2x)= 45 degrees


Finance/269292: B. Mary just deposited $33,000 in an account paying 7% interest. She plans to leave the money in this account for eight years. How much will she have in the account at the end of the seventh year? toins5@aol.com
1 solutions

Answer 197391 by rfer(12644) About Me  on 2010-02-13 20:26:41 (Show Source):
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FV=P(1+.07)^7
FV=33000(1.07)^7
FV=33000(1.60)
FV=$52,800


Miscellaneous_Word_Problems/269293: A certain model of car with a normal engine costs $11,000 to purchase and 22 cents a mile to operate. The same car with a fuel-injection engine costs $11,300 to purchase but only 20 cents a mile to operate. After how many mile does the total cost of both cars become the same?
1 solutions

Answer 197390 by rfer(12644) About Me  on 2010-02-13 20:22:28 (Show Source):
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11000+.22x=11300+.2x
.02x=300
x=47000 miles


Money_Word_Problems/268869: A car salesperson receives a flat weekly salary of $260 plus a 3% commission on the total dollars of all sales made. What are the total sales for a week in order to earn $1,220?
THANKS!!! HAVE A GREAT DAY
1 solutions

Answer 197207 by rfer(12644) About Me  on 2010-02-12 22:02:14 (Show Source):
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1220-260=960
960/.03=$32,000


Graphs/269068: The price P for a watermelon varies directly with its
weight w.
a) Write a formula for this variation.
b) If the price of a 30-pound watermelon is $4.20, then
what is the price of a 20-pound watermelon?
1 solutions

Answer 197206 by rfer(12644) About Me  on 2010-02-12 21:56:23 (Show Source):
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4.2/30=x/20
30x=84
x=$2.80


Travel_Word_Problems/269012: How long would it take to go 3 miles while traveling at 70 mph?
1 solutions

Answer 197201 by rfer(12644) About Me  on 2010-02-12 21:54:05 (Show Source):


Triangles/268943: The hypotenuse of a right triangle is 14. One of the triangles side lengths is 6. Find length of the remaining side.
(Round your answer to one decimal place if needed.)
1 solutions

Answer 197038 by rfer(12644) About Me  on 2010-02-12 12:58:15 (Show Source):
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a^2+b^2=c^2
6^2+b^2=14^2
36+b^2=196
b^2=160
b=12.6


Triangles/268937: a triangle has a height of 12 cm and an area of 60 cm. What is the area of a similar triangle with a height of 6 cm?
1 solutions

Answer 197036 by rfer(12644) About Me  on 2010-02-12 12:54:48 (Show Source):
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12/60=6/x
12x=360
x=30 sq cm


Percentage-and-ratio-word-problems/268931: A merchant buys goods at 25% off the list price. He desires to mark the goods so that he can give a discount of 20% on the marked price and still clear a profit of 25% on the selling price. What per cent of the list price must he mark the goods?
(A) 125% (B) 100% (C) 120% (D) 80%. (E) None of these.
1 solutions

Answer 197035 by rfer(12644) About Me  on 2010-02-12 12:52:20 (Show Source):


Numbers_Word_Problems/268744: One number is 3 more than twice another number. find the larger number is their sum is -15
1 solutions

Answer 196955 by rfer(12644) About Me  on 2010-02-12 00:53:31 (Show Source):
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x+2x+3=-15
3x=-18
x=-6
-6+-6+3=-9