Algebra practice 4th edition book 1 pg 163

[dmwojo83]

My question is regarding #12 on page 163 out of Algebra practice book #1
"If the total weight of the pumpkins in a pumpkin patch increases by a factor of 10 while the number of pumpkins decreases by 20%, by what factor does the average weight of a pumpkin in the pumpkin patch increase?"

I understand the explanation up until the very end...can you please explain why 25 is divided by 2?

Thanks!

[tommywallach]

The old average weight was 2 pounds. The new average weight is 25 pounds. They want to know by what factor it increased. That just requires putting the latter over the former: 25/2.

Here's a more obvious example question:

4 is bigger than 2 by what factor?

4/2 = 2

It's bigger by a factor of 2.

Hope that helps!

-t