90 trucks- for every 2 cars there are 5 trucks
7 brown, 3 yellow, 8 red...total of 18 cards
there are 15 cards not yellow and a total of 18 cards....so the probability of not picking a yellow card is : 15/18 rounds to 5/6
distance = speed * time
the first bus speed = x
second bus = x - 12
the sum of distance = 765 miles
first distance = 6x
second distance = 6 (x -12)
6x + 6(x-12) = 765
x + x -12 = 127.5
2x = 139.5
x = 69.75 mi/h which is the faster bus
the second bus speed = 57.75 mi/h
6.5 liters per 100 km travelled. 30% of 5 is 1.5, so adding this to the original amount results in 6.5
