2 boxes of cereal cost $5:16 how much would 3 boxes of cereal cost

Multiply the price times the number of boxes

Ok, we know that 2 boxes cost $5.16. We can divide this price by 2 to find the price of one. 5.16/2 = $2.58, so we now know that one box costs $2.58. We can multiply this by 3 to find the cost of three boxes, $7.74. Three boxes cost $7.74