Question

Samantha and Mia each left Julia’s house at the same time. Mia walked north at 7 kilometers per hour. Samantha ran west at 11 kilometers per hour. How far apart were they after one hour? Round the answer to the nearest tenth.


7.7 km
8.4 km
13.0 km
18.0 km

Answer 1

We have to use Pythagoras theorem to find our answer. Pythagoras says
${a}^{2} + {b}^{2} = c {}^{2}$
With c representing the hypothenusa.

Filling in the formula gives us
${7}^{2} + {11}^{2} = {c}^{2}$
$49 + 121 = {c}^{2}$
$c {}^{2} = 170$
$c = \sqrt{170} = 13.03...$

Hence, after one hour of walking Samantha and Mia are about 13 km away from each other.

Answer 2

Answer: 13 km.............