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11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299, >>NextTrigonometry-basics/334035: A 12 foot ladder leans against a wall at a 70% angle with the ground.
What is the distance between the ground and the top of the ladder?
1 solutions
Answer 239324 by mananth(12270) on 2010-08-23 00:03:55 (Show Source):
You can put this solution on YOUR website!A 12 foot ladder leans against a wall at a 70 deg angle with the ground.
What is the distance between the ground and the top of the ladder?
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the ground ladder and the wall form a right triangle
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hypotenuse = 12
angle = 70 deg.
vertical height = ?

perpendicular height = 
= sin(70)* 12
= 11.2 feet
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Rate-of-work-word-problems/334039: It takes one painter 12 days to paint a house, it takes another painter 8 days to paint a house the Identical size. How many days will it take to paint a house together?
1 solutions
Answer 239320 by mananth(12270) on 2010-08-22 23:51:02 (Show Source):
You can put this solution on YOUR website!It takes one painter 12 days to paint a house,
he paints 1/2 of the house in 1 day.
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it takes another painter 8 days to paint a house
he paints 1/8 of the house in 1 day.
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together they paint 1/8 + 1/12 of the house in 1 day
= LCM =24
3+2 / 24
= 5/24 of the job they do in 1 day
so they will take 24/5 days together
= 4.8 days to complete the job together.
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Geometry_Word_Problems/334030: A fortress has been built on top of a cliff. You measure the angle of elevation of the top of the cliff from a point 200 ft horizontally away from the base of the cliff to be 30' and the angle of elevation of the top of the fortress wall from the same point to be 45'. What is the height of the fortress wall? 1 solutions
Answer 239319 by mananth(12270) on 2010-08-22 23:47:42 (Show Source):
You can put this solution on YOUR website!Angle of elevation of cliff base = 30/60 deg ( 60 ' = 1 deg)
distance on ground = 200 feet
so height of cliff = 200*Tan(1/2)
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Angle of elevation of wall top = 45/60 deg
distance on ground = 200 feet
so height of cliff+ wall = 200*Tan(3/4)
200*tan(3/4)-200*tan(1/2) = height of wall
= 77.05 feet
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Linear-equations/334032: (0,2); 2x+9y=7 write the equation of the line containing the given points and perpendicular to the given line. y=mx+b format 1 solutions
Answer 239318 by mananth(12270) on 2010-08-22 23:33:50 (Show Source):
You can put this solution on YOUR website!(0,2);
2x+9y=7
add-2x to both sides
2x-2x+9y=-2x-7
9y=-2x-7
divide by 9
y= -2/9x -7/9
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slope = -2/9
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the slope of a lin perpendicular to this line will be 9/2
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y = mx +b
(0,2)
plug the value of x,y to get b
2= 0+b
b=2
y= 9/2 *x +2 is the line
..
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Linear_Equations_And_Systems_Word_Problems/333754: A total of $20,000 is to be invested in bonds and some in certificates of deposit. If the amount invested in bonds is to exceed that of certificates of deposit by $2,000, how much will be invested in each type? 1 solutions
Answer 239167 by mananth(12270) on 2010-08-22 09:32:06 (Show Source):
You can put this solution on YOUR website!let amount invested in certificates be $x
the amount invested in bonds will be (20,000-x)
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(20,000-x)= x+2000
20,000-x= x +2000
2x= 18,000
x = 9000 amount invested in certificates
$ 11,000 will be invested in bonds
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Surface-area/333744: a circle with a 9cm diameter, has a piece cut out with a degree of 44. how do you work out the lenghtof the piece? and what is the circumference of the whole circle and how do you work that out? 1 solutions
Answer 239161 by mananth(12270) on 2010-08-22 06:32:00 (Show Source):
You can put this solution on YOUR website!You need the length of the arc of the circle.
angle = 44 deg
arc length = 44*(pi/180) * 4.5
= 3.46 cm
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circumference = pi*9= 28.27 cm
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Numbers_Word_Problems/333671: Four times the larger number was 11 greater than 7 times the smaller number. If the smaller number was 8 less than the larger number, what was the smaller number? 1 solutions
Answer 239160 by mananth(12270) on 2010-08-22 06:23:15 (Show Source):
You can put this solution on YOUR website!let larger number be x
smaller number be y
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4x =7y+11
4x-7y=11...................1
x-y=8......................2
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multiply equation 2 by -4 and add to equation 1
-4x+4y+4x-7y=-32+11
-3y=-21
y=7
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x-y =8
x=8+y
x=15
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Miscellaneous_Word_Problems/333742: Solve the quetion according to "Volume and Surface Area" formula
A rectangular tank measures 4m long,2m wide and 4.8m high.Intially it is half filled with water .Find the depth of water in the tank after 4000 liters more of water added to it . 1 solutions
Answer 239159 by mananth(12270) on 2010-08-22 06:17:56 (Show Source):
You can put this solution on YOUR website!A rectangular tank measures 4m long,2m wide and 4.8m high.Intially it is half filled with water .Find the depth of water in the tank after 4000 liters more of water added to it .
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Volume of full tank = 4*2*4.8 =38.4 cu.m
1/2 volume = 38.4 /2 = 19.2 cu.m
19.2 cu. m = 19.2 *1000 liters
= 19200 liters
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19200 liters = 2.4 m height ( half tank)
4000 liters = ?
= 2.4*4000/19200
=0.5 meters height for 4000 l
Total depth will be 2.4 + 0.5= 2.9 m
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Travel_Word_Problems/333635: Karen left her house heading east, and her sister left two hours later heading west at a rate 5 mph faster than Karen. Six hours after Karen left, she and her sister were 600 miles apart. How fast was Karen moving? 1 solutions
Answer 239158 by mananth(12270) on 2010-08-22 06:03:40 (Show Source):
You can put this solution on YOUR website!Karen left her house heading east,
her sister left two hours later heading west at a rate 5 mph faster than Karen.
Six hours after Karen left, she and her sister were 600 miles apart. How fast was Karen moving?
Karen speed be x mph
Karen has traveled 6x miles (in 6 hours)
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sister x+5 mph .
Sister has traveled 4(x+5) miles. left 2 hours later.
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4(x+5)+6x =600
4x+20+6x=600
10x+20=600
10x=600-20
10x=580
x= 58 mph speed of Karen
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absolute-value/333739: Find, to the nearest degree, the angle made with the positive direction of the x-axis if y+x=3. Give your answers as obtuse angles 1 solutions
Answer 239157 by mananth(12270) on 2010-08-22 05:51:12 (Show Source):
You can put this solution on YOUR website!y=3-x
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(1,2)... x=1, y=2
(2,1)
(3,0)
(-1,4)
(-2,5)
(0,3)
From the various points obtained by plugging the values of x in the equation
The line intercepts the x & yaxis at x=3 & y=3.
The line forms an isoscles triangle with the axes.
So the angle will be 45 deg
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Linear-equations/333699: Find the ordered pair solution to the following system of equations (Use any method):
3x – y = 5
2x + 5y = -8
1 solutions
Answer 239154 by mananth(12270) on 2010-08-22 05:35:32 (Show Source):
You can put this solution on YOUR website!3x – y = 5
2x + 5y = -8
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multiply equation 1 by 5 and add it to equation 2
15x-5y=25
2x+5y=-8
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17x=17
x=1
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plug value of x in equation 1
3-y=5
y=-2
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Linear-equations/333700: Solve the following word problem (Hint: setup and solve a system of equations):
One number plus twice another number gives a sum of 42. The difference of these same two numbers equals –3.
Find the two numbers
1 solutions
Answer 239152 by mananth(12270) on 2010-08-22 03:16:24 (Show Source):
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Length-and-distance/333722: Any assistance is greatly appreciated:
A runner is training for a marathon on a track whose straightaways are 500 ft and semicircles have a diameter of 40 ft. What is the total distance he will run if he runs the track 13 times? What is his average speed in MPH if it takes him 40 minutes and 35 seconds after 13 times?
Thank you for your time. 1 solutions
Answer 239149 by mananth(12270) on 2010-08-22 03:02:18 (Show Source):
You can put this solution on YOUR website!length of 1 round = 500+500+ pi*40 ( 2 semicircles on either end)
=1000+40*pi
=1125.66 feet is the length of 1 lap.
13 laps will be
13 * 1125.66
=14633.62 feet
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5280 feet = 1 mile
14633.62 feet = 146322.62/5280
= 2.77 miles
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40 minutes 35 seconds is the time taken for 13 laps.
=2400+35
= 2435 seconds
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2435/3600 = 0.676 hours
speed = distance / time
=2.77 miles/0.676
= 6.9 mph
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Money_Word_Problems/333726: if mrp of product is 2250 and i deduct 30% on it then it comes to 1575 but if i add 30% to it that will not come to 2250 1 solutions
Answer 239147 by mananth(12270) on 2010-08-22 02:23:28 (Show Source):
You can put this solution on YOUR website!while calculating discount you are taking it on mrp
2250*30/100=675
2250-675=1575.
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but while doing the reverse you may be taking 30% 0f 1575 which is incorrect.
take 30% of 2250 = 675
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add it back to 1575 = 2250..
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OR
when sale price is 70 the mrp will be 100
when it is 1575 the mrp will be
1575*100/70
= 2250
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Linear-equations/333725: Let C = Celsius degree and F= Fahrenheit degree scales for temperature. Assuming that relation between C and F is linear and drawing F on vertical axis. Two data points on the line relating C and F are (5, 41), (25, 77) Find the equation relating C and F. Can it be applied for practical purposes? 1 solutions
Answer 239145 by mananth(12270) on 2010-08-22 02:14:02 (Show Source):
You can put this solution on YOUR website!(5, 41), (25, 77)
the slope of the line passing through the above points =
77-41 / 25-5
=36/20
=9/5 = m the slope
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general equation of line = y = mx +b
plug value of any point and the slope m in the equation
(5,41)
41=9/5 *5 +b
41=9+b
41-9=b
b=32
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so the general equation will be
y = 9/5 x + 32
f is drawn on they axis and c on the x axis
f= 9/5 c + 32
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Plot the points and join the points to get a graph as given below.
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