Dr. Green has to multiply the weight of the team’s bug spray bottles, 7 x 90 grams. To solve this, he writes out the equation 7 x 9 x 10.

Why does this strategy work?

Respuesta :

It works because 7 x 9 x 10 is the same thing as 7 x 90, since 9 x 10 is just 90. So basically he is just writing more but the answer will still be the same.