Sydney's age = x
Devaughn's age= 3x
So you get the equation:
x+3x=24
4x=24 (combine like terms)
x=6 (divide both sides by 4)
His sister will be 20, right!
Decreasing by 4 each time
so 34 decreased by 4 is 30
A is answer
Find the total distance between the two runners:
5.1 + 4.1 = 9.2 km apart.
We want to calculate the distance each runner does:
Runner A distance = X km, rate = 8.5 km/ hr.
Time = X / 8.5
Runner B distance = (9.2 - x) Total distance between the runners minus what runner A runs equals where they meet).
Rate = 7.4 km/hr.
Time = (9.2-x) / 7.4
Now to find where they meet set the two equations equal:
x / 8.5 = (9.2-x) / 7.4
Cross Multiply:
7.4x = 78.2 - 8.5x
Add 8.5x to both sides:
15.9x = 78.2
Divide both sides by 15.9:
x = 78.2 / 15.9
x = 4.918 = 4.9 km.
Since X is the distance runner A runs, subtract that from his distance from the flag pole:
5.1 - 4.9 = 0.2
The runners meet 0.2 km west of the flag pole.
