Alex and freddy collect stamps. the number of stamps in alex’s collection is in ratio 3: 5 to the number of stamps in freddy’s collection. if freddy gives alex 10 stamps, the ratio will change to 7: 9. how many stamps are in both collections together?

let soccer = x and golf = y

part a

1st equation: x + y = 125

2nd equation: x = y +45

part b

replace x in the 1st equation with the 2nd one:

y + 45 + y = 125

simplify:

2y + 45 = 125

subtract 45 from each side:

2y = 80

divide both sides by 2:

y = 80/2

y = 40

she plays golf for 40 minutes.

part c

no because she plays soccer for 45 minutes longer than golf 40 +45 =   85 minutes, not 80 minutes.

you have 6 cupcakes