Question

James' teacher asked him to rewrite the sum 60 + 90 as the product of the GCF of two numbers and a sum. James wrote 3(20 + 30). What mistake did James make? how should he have written the sum?

Answer 1

James incorrectly identified 3 as the GCF for 60 and 90. The correct GCF is 30, and thus the sum should be rewritten as 30(2 + 3), where 30 is the GCF, and 2 and 3 are the resulting factors of 60 and 90 when divided by 30.

Step-by-step explanation:

James' mistake in rewriting the sum 60 + 90 as the product of the GCF of two numbers and a sum is that he chose the incorrect GCF. The GCF (Greatest Common Factor) of 60 and 90 is actually 30, not 3.

To correctly express the sum using the GCF, it should be written as 30(2 + 3), because when we factor out 30 from both numbers, we're left with 2 and 3, which when multiplied back by 30, gives us the original numbers 60 and 90, respectively.