It works because even if the numbers are broken apart, you are still multiplying the numbers by their values, it's only different because once broken apart, it's in expanded form instead of standard form. It also makes multiplication easier since you don't have to deal with such large numbers.
Billy drove 3.75 miles. You find the answer by dividing 7.5 by 2
Tony is 24 miles from the house.
Jake is 10 miles from the house.
They are 26 miles apart.
The fractions are arranged in order from greatest to least.