3w - 10 + w = 90
what does w equal to?

3w-10+w=90

The first thing you want to do is combine like terms
3w-10+w=90
Add 10
3w+w=100
And combine 3w and w
4w=100

To get w alone, divide 100 by 4
100/4=25
w=25

Hope that helps :)

You need to show the box plots