sahar travels the first 7 hours of his journey at 50 mph speed and the remaining 8 hours at 40 mph ...
sahar travels the first 7 hours of his journey at 50 mph speed and the remaining 8 hours at 40 mph speed. What is the average speed of sahar's travel in mph?
Answer/Solution
44.6 mph
Steps/Work
Explanation :
Average speed=Total Distance/Time.
Total distance travelled by sahar = Distance covered in the first 7 hours + Distance covered in the next 8 hours.
Distance covered in the first 7 hours = 7×50=350 miles
Distance covered in the next 8 hours= 8×40=320 miles
Therefore, total distance travelled = 350+320=670 miles.
The total time taken = 7+8=15hours.
Hence, the average speed =670/15= 44.6 mph.
Answer : B
Average speed=Total Distance/Time.
Total distance travelled by sahar = Distance covered in the first 7 hours + Distance covered in the next 8 hours.
Distance covered in the first 7 hours = 7×50=350 miles
Distance covered in the next 8 hours= 8×40=320 miles
Therefore, total distance travelled = 350+320=670 miles.
The total time taken = 7+8=15hours.
Hence, the average speed =670/15= 44.6 mph.
Answer : B