Delvin, Eric and Felicia have 478 stickers. Delvin has 4 times as many stickers as Eric. Felicia has 397 stickers more than Delvin. How many stickers does Delvin have?

478 stickers,

4x -> Delvin

397 + 4x -> Felicia

x -> Eric

478 = 4x + 397 + 4x + x

478 = 9x + 397

478 - 397 = 9x

81/9 = 9x/9

9 = x

Delvin = 4x

= 4(9)

= 36

36 stickers