Question

Brianna left the bookstore traveling 32 mph. Then 3.2 hours later, Sonya left traveling the same direction at 44.8 mph. How long until Sonya catches up with Brianna

Answer 1

Answer:

8 hours

Step-by-step explanation:

Let t hours be the time needed Sonya to catch up Brianna.

Sonya:

Time = t hours

Rate = 44.8 mph

Distance $=D_S$ miles

Brianna

Time $=t+3.2$ hours

Rate = 32 mph

Distance $=D_B$ miles

Note that $D_S=D_B,$ because Sonya must catch up Brianna.

Use formula $D=r\cdot t$

Hence,

$44.8t=32(t+3.2)$

Solve this equation:

$44.8t=32t+32\cdot 3.2\\ \\44.8t-32t=102.4\\ \\12.8t=102.4\\ \\t=8$