Going upstream: 432 km / 6 hours = 72 km/h
Going downstream: 384 km / 4 hours = 96 km/h
Going upstream against the current means that the effective speed is:
r_boat - r_current = 72
Meanwhile, going downstream with the current means;
r_boat + r_current = 96
Adding both equations (to cancel out r_current) gives:
2r_boat = 72 + 96
r_boat = 84 km/h
Substituting back into one of the original equations: r_current = 12 km/h.
Add 3x and 2x together to get 5x. Then do 88+108-6 and you get 190. To find x now all you have to do is use 5x+190=360 to get x.
360 -190= 170 now you have 5x=170 divide 170/5 and that will give u the value of x.
Answer:
1. It means they saved $125 in 10 months
2. y = 25/2
