let x = the number of green apples, let 4x = the number of red apples
4x + x = 50 Set up the quation
5x = 50 Combine like terms
---- ---- Divide by 5 on both sides to get x alone
5 5
x = 10 green apples
4x = 4(10) = 40 red apples
40 - 10 = 30. Suzanne bought 30 more red apples than green apples.