Jenna walks 4 miles in 1 hour. At this rate how many miles can she walk in 3.5 hours

Question

I'm working on ratios involving complex fractions

Answer 1

If Jenna walks 4 miles in 1 hr; then she can walk 4 x 3.5=14 miles in 3.5hrs.

Answer 2

Ratios can be determined through proportions! Here is how you would set it up: you would have both the numerator and denominator having the same unit while the fraction represents one object.

For this proposed problem I would set up one of the fractions for Jenna's walking rate. The numerator would have the miles over time. The other fraction would have the unknown miles over the known time. This makes it so the numerators have the same unit (distance in mi) while the denominators also share a unit (time in hr).

Here are the fractions with the numbers in place: 4mi/1 hr = x mi/3.5 hr. So now to solve for x, you cross multiply. This is done by making a zigzag pattern with the math by multiplying diagonally first before dividing the numbers so you would end up at the spot where x would be. So here, you would multiply 3.5 by 4 (which is 14) and then divide by 1. The answer here would be 14mi (14÷1=14)