### Instruction: Let A = 1, B = 2, C = 3, ..., Z = 26. The product value of a word is equal to the product of the values of its letters. For example, CAB has a product value of 3 $\times$ 1 $\times$ 2 = 6. What common English word has a product value of 715? It does not have to be of length 3.### Response: This is an interesting problem because it involves both math and language.
The first thing I notice is that 715 is a multiple of 5, so one of the letters in the word must be E, which has a value of 5.
The other factor of 715 is 143, which is not prime.
In fact, 143 = 11 $\times$ 13, so the other two letters in the word must be K and M, which have values of 11 and 13 respectively.
The only common English word that has these three letters in any order is MAKE.