SOLUTION: need your help, urgent! help!help!help! 1. It takes jun thrice the number of days it takes Peter to mow a lawn. When the two boys work together, the job is completed in three day

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Question 204924: need your help, urgent!
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1. It takes jun thrice the number of days it takes Peter to mow a lawn. When the two boys work together, the job is completed in three days. How long does it take each boy to do the job alone?
2. Two planes leave NAIA at 4 p.m., one traveling east at 8:50 kph and the other, west at 750 kph. At what time will they be 4000 km apart?
3. An airplane which travels 180 miles per hour leaves the airport 8.5 hours after a ship has sailed. If it overtakes the ship in one hour and 30 minutes, find the rate of the ship.
4. Rolly and Romy are 15 km apart and are walking towards each other. If rolly is walking at rate of kph and romy at a rate of 3 kph, in how many hours will they meet?
5. Albert sets out on a hike. After walking for a while at 6 kph, he discovers that he has forgotten his lunch. A passing bus takes him back home at 30 kph. How far did he walk if he was gone for one hour?

6. The length of a rectangle is six more than half its width. If the perimeter of the rectangle is 18 units, what are the dimensions of the rectangle?
7. The second angle of a triangle is 10 degrees more than half the measure of the first angle. The third angle is 10 degrees less than four times the second angle. What are the measures of the three angles in the triangle?
Answer by ankor@dixie-net.com(22740) (Show Source):
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Here are the equations for these problems
:
1. It takes jun thrice the number of days it takes Peter to mow a lawn.
When the two boys work together, the job is completed in three days.
How long does it take each boy to do the job alone?
:
Let t = time required for Peter to mow the lawn
then
3t = time required for Jun to mow the lawn
and
the completed job = 1
+ = 1
:
;
2. Two planes leave NAIA at 4 p.m., one traveling east at 850 kph and the
other, west at 750 kph. At what time will they be 4000 km apart?
:
let t = time required (add to 4 PM)
850t + 750t = 4000
:
:
3. An airplane which travels 180 miles per hour leaves the airport 8.5 hours after a ship has sailed. If it overtakes the ship in one hour and 30 minutes, find the rate of the ship.
:
r = speed of the ship
1.5(180) = r(8.5+1.5)
:
:
4. Rolly and Romy are 15 km apart and are walking towards each other. If rolly is walking at rate of __ kph and romy at a rate of 3 kph, in how many hours will they meet?
:
Let t = time required for them to meet
_t + 3t = 15
:
:
5. Albert sets out on a hike. After walking for a while at 6 kph, he discovers that he has forgotten his lunch. A passing bus takes him back home at 30 kph. How far did he walk if he was gone for one hour?
:
let d = dist walked, (also dist by bus)
+ = 1
:
:
6. The length of a rectangle is six more than half its width.
If the perimeter of the rectangle is 18 units, what are the dimensions of the rectangle?
:
x = the width
then
(.5x+6) = the length
2(.5x + 6) + 2x = 18
:
:
7. The second angle of a triangle is 10 degrees more than half the measure of
the first angle. The third angle is 10 degrees less than four times the second angle.
What are the measures of the three angles in the triangle?
:
let x = 1st angle
then
(.5x+10) = 2nd angle
and
4(.5x+10) - 10 = 3rd angle
:
x + (.5x+10) + (4(.5x+10)-10) = 180