He spent $7 on cereal because 2 x 3.5 = <<2*3.5=7>>7
He spent $1 on bananas because 4 x .25 = <<4*.25=1>>1
He spent $2 on apples because 4 x .5 = <<4*.5=2>>2
He spent 13 on everything but the cookies because 3 + 7 + 1 + 2 = 13
He spent $12 on cookies because 25 - 13 = <<25-13=12>>12
Each box of cookies is $6 because 3 x 2 = <<3*2=6>>6
He bought 2 boxes of cookies because 12 / 6 = <<12/6=2>>2
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