Question

Jack and Jane leave their home traveling in opposite directions on a straight road. Jack drives 20 mph faster than Jane. After 4 hours, they are 250 miles apart. What Jack's rate is and what Jane's rate is

Answer 1

Jane's rate is 21.25 mph.

Jack's rate is 41.25mph

Step-by-step explanation:

Let x represent Jane's speed.

Jack's speed will be x+20.

Their combined speed is;

`x+x+20=2x+20`

After 4 hours, their combined distance covered is 250 miles;

`\begin{gathered} 4(2x+20)=250 \\ 8x+80=250 \end{gathered}`

solving for x;

`\begin{gathered} 8x=250-80 \\ 8x=170 \\ x=(170)/(8) \\ x=21.25\text{ mph} \end{gathered}`

Jane's rate is 21.25 mph.

Since jack's rate is 20 mph faster than Jane's rate.

Jack's rate is;

`\begin{gathered} 21.25+20 \\ =41.25\text{mph} \end{gathered}`

Jack's rate is 41.25mph