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3 years ago

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During a race, a runner’s time was 4 seconds at the 36-meter mark and 6 seconds at the 57-meter mark. What was the runner’s aver

age speed, in meters per second, for the time interval between 4 seconds and 6 seconds? (A) 2.1 (B) 9.0 (C ) 9.3 (D)9.5 (E) 10.5
i need help ASAP ):

2 answers:

KIM [24]3 years ago

8 0

Answer:

The average speed of runner is given by option d) 10.5 meters per second.

Step-by-step explanation:

We are given the following information in the question:

A runner’s time was 4 seconds at the 36-meter mark.

A runner’s time was 6 seconds at the 57-meter mark.

Formula:

$\text{Average speed} = \displaystyle\frac{y_2-y_1}{x_2-x_1}\\\\\text{where}, y_2, y_1 \text{are the distances at time} x_2, x_1 \text{respectively.}$

Putting the given values in the question, we have:

$\text{Average speed} = \displaystyle\frac{57-36}{6-4} = \frac{21}{2} = 10.5\text{ meter per second}$

Hence, the average speed of runner is given by option d) 10.5 meters per second.

Arturiano [62]3 years ago

6 0

Answer:

E

Step-by-step explanation:

57 - 36 = 21 6 - 4 = 2 seconds

21 ÷ 2 = 10.5

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