Question

Quinn used compensation to find the product of 37x4. First, she found 40x4=160. Then she adjusted that product by adding 3 groups of 4 to get her final answer of 172. What did she do incorrectly?

Answer 1

Quin is adding the compensation needed instead of subtracting. First she calculated 40x4. She is trying to find 37x4. To do this, she would have to instead gather all the data: 3x4 = 12 40x4 = 160 Subtract instead of add: 40x4 - 3x4 = ? 160 - 12 = 148 The answer is 148.