#### Answer

The lifeguard will enter the water 40 yards left from the position.

#### Work Step by Step

As the triangles are similar:
$\frac{20}{30}=\frac{x}{100-x}$
Then we just need to solve the equation for x:
$20(100-x)=30x$
$2000=50x$
$x=40$

Published by
Pearson

ISBN 10:
0321671775

ISBN 13:
978-0-32167-177-6

The lifeguard will enter the water 40 yards left from the position.

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