There should be 20 boys.
32/(5+3)=4.
4*5=20.
Both distances 3966 and 4746 were done in 6 hours, so the speeds are:
speed against wind = 3966/6=661 km/h (difference of airplane and wind)
speed with wind = 4746/6=791 km/h (sum of airplane and wind)
The speed of airplane is greater than that of the wind, so this is a sum and difference problem.
Greater speed (plane) = (sum+difference)/2=(791+661)/2=726 km/h
Lesser speed (wind) = (sum-difference)/2 = (791-661)/2 = 65 km/h
Given equations:
P=w+2
p=7w-16
Compare both equations
7w-16=w+2
Add 16 to both sides.
7w=w+18
Subtract w from both sides.
6w=18
Divide both sides by 6.
w=3, which is the age of Winnie.
Now Peter's age=3+2=5 years
Option A is the correct method to find the age of Peter and Winnie.
Keep the inequality sign the same
x= -15/4 => x= -3 3/4 or x= -3.75