Chapter 2, Problem 7STP

To determine

To Choose: The correct option.

Answer to Problem 7STP

A correct answer is an option (A).

Explanation of Solution

Given:

The given table is shown below

Runner	Distance covered (km)	Time (min)
Ling-Long	12.5	42
LaToya	7.8	38
Bill	10.5	32
Jose	8.9	30

Formula used:

The average speed is

  $s=\frac{d}{t}$  ...... (1)

Here, $d$ and $t$ are distance and time taken to travel.

Calculation:

Substitute 12.5 km for $d$ and 42 min for $t$ in equation (1)

  $\begin{array}{l}s=\frac{12.5\text{km}}{42\min }\\ \boxed{s=0.30\text{km/min}}\end{array}$

Conclusion:

Hence,the average speed of Ling-Ling is $0.3\text{km/min}$ .