Ok so in order to do that you need a calculator
Suppose Alex has 3x stamps, Freddy has 5x stamps. After Freddy gives Alex 10 stamps, Alex has 3x+10 while Freddy has 5x-10
the new ratio is 7 to 9, so we have the equation: (3x+10)/(5x-10)=7/9
9(3x+10)=7(5x-10)
27x+90=35x-70
160=8x
x=20
So Alex has 3*20=60 stamps while Freddy has 5*20=100. Together they have 160
Y = 3x + 48 where x is your number of years. I got 48 by multiplying 4 and 12 since there are 12 inches in a foot. (:
Answer
Its around 30% but their is about 55 other marbles
Step-by-step explanation:
Y = x + 14 (the larger bus has 14 more seats)
2x + y = 65 ( 2 x two times the seats , as it makes 2 trips the smaller van so the seats will be full twice maximum)
2x + x + 14 = 65 (sub the value of y = x+14 in the second equation)
3x = 51
x = 17 seat (smaller)
y = 31 seat (larger)
