Question

7. Mahmoud runs to a marker and back in 15 minutes. His speed on

the way to the marker is 5 m/s and his speed on the way back is
4 m/s. Find the distance to the marker.​

Answer 1

2000 meters

Explanation:

From the above question

Total time = 15 minutes

Converting minutes to seconds

1 minute = 60 sec

15 minutes = x

Cross Multiply

x = 60 × 15 = 900 seconds

Hence, 900 seconds = Total time

Total time = Time to the marker + Time from the marker

From the question, we are given the Speed to the marker = 5 m/s

Speed from the marker = 4 m/s

Time = Distance/speed

Let the distance be represented by x

Hence:

x/4 + x/5 =900

Multiply all through equation by Lowest Common Denominator = 20

5x + 4x= 900×20

9x = 900 ×20

Divide both sides by 9

9x/9 = 900 × 20/9

x = 2000 meters

Therefore, the total distance to the marker = 2000 meters