Xiao’s teacher asked him to rewrite the sum 60+90 as a product of gcf of two numbers and a sum . xiao wrote 3(20+30.what mistake did xiao make ? how should he have written the sum

The first thing we must do for this case is find the factors of each of the numbers.

We have then:

60: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60

90: 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90

Therefore the GCF is given by:

So, by rewriting the sum we have:

The error is not having written the GCF multiplying.

Xiao did not write the sum as the product of GCF and the sum of two numbers.

The correct expression is:

typically if you want , you would actually put questions here for us to you. but hey, that's just me. maybe someone will magically answer the questions for you without knowing what they are.