Question

1. a submersible descends at an average rate of 7.1 m/min. express the depth below the surface after 4.6 min as a rational number. a. -32.66 m b. -11.7 m c. +32.66 m d. 11.7 m

Explanation:

Step1: Identify the rate and time

The rate of descent $r = 7.1$ m/min and time $t=4.6$ min.

Step2: Use the distance - rate - time formula

The depth $d$ is given by $d = r\times t$. So $d=7.1\times4.6$.

Step3: Calculate the product

$7.1\times4.6=(7 + 0.1)\times4.6=7\times4.6+0.1\times4.6=32.2+0.46 = 32.66$ m. Since it is descending (going downwards), the depth is negative. So the depth is $- 32.66$ m.

Answer:

a. $-32.66$ m