Tom has to walk 3/8 of a mile to school. if he walks 4/5 of the way, how gas has he walked?

The distance Tom has to walk is - 3/8 of a mile 
from this distance he has only walked a fraction of 4/5. 
he has walked 4/5th of the distance being 3/8 of a mile 
4/5th of 3/8
we need to multiply the 2 fractions here as 'of' is the operator here.
4/5 x 3/8

since its multiplication denominators are multiplied with denominators and numerators are multiplied with numerators

we can simplify this fraction further 


3/10th of a mile = 0.3 miles he has walked