Question

Richard goes on a 6-mile jog one morning. He jogs the first two miles at an average speed of 6 mph. He progressively slows down; his average speed during the next two miles is 4 mph. He walks the remaining two miles at an average speed of 3 mph. What is Richard's average speed, in miles per hour?

Answer 1

Average speed = 4 mph

Explanation:

Given as

Total distance to travel = 6 mile

now, for first 2 mile the avg speed = 6 mph

for next 2 mile the avg speed = 4 mph

and for rest 2 mile the avg speed = 3 mph

so, the average speed of the Richard =
`(3)/((1)/(6)+(1)/(4)+ (1)/(3)  )`

Total Avg speed =
`(3)/((9)/(12) )`

Or, =
`(3)/(9)`×12

= 4

So the total Average speed = 4 mph (Answer)