20miles increased by 30%=new mileage added
20x.3= 6
6 miles more than his previous distance so...
6+20= 26
NOTE you can also use 1.3 instead of .3 as the percent to get the answer with out addition.
Hi there!

We know that the equation for the volume of a pyramid is:
V = 1/3(bh)
We know that:
V = 200 km³
b = 12 × 5 = 60 km²
We can plug these into the equation:
200 = 1/3(60)(h)
Simplify:
200 = 20h
Divide both sides by 20:
200/20 = 20h/20
h = 10 km
True i think but i'm not postive