Distance Rate Time problem

Question

One morning, Ryan remembered lending a friend a bicycle. After breakfast, Ryan walked over to the friend’s house at 3 miles per hour, and rode the bike back home at 7 miles per hour, using the same route both ways. The round trip took 1.75 hours. What distance did Ryan walk?

Answer 1

HINT:

Let the distance between the friend’s house from Ryan's is $d$ miles

As we know speed $\displaystyle =\frac{\text{distance}}{\text{time}}\implies $ time $\displaystyle =\frac{\text{distance}}{\text{speed}}$

So, to go to the friend’s house, he took $\frac d3$ hours

While returning he took $\frac d7$ hours

So, $\frac d3+\frac d7=1.75$

Answer 2

$$3 \cdot t = d$$

$$7 \cdot (1.75 - t) = d$$

Solve two equations in two unknowns to determine $d$: the distance walked (the distance to or from the friend's house.)

Or you could simply solve for $t$ (time), then substitute $t$ into equation $(1)$ to obtain $d$ (distance), knowing $$3 \cdot t = 7 \cdot (1.75 - t)$$

Answer 3

As given total time taken is 1.75 hrs So assume total distance is d than 1.75=d/3+d/7

1.75=10d/21 d=3.675miles ans walking distance