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?  Select the correct option
A) 44.3 mph	B) 44.6 mph	C) 44.9 mph	D) 44.1 mph	E) 44.2 mph
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 = 7Ã—50=350 miles   Distance covered in the next 8 hours= 8Ã—40=320 miles   Therefore, total distance travelled = 350+320= 
<gadget id="calculator">350+320</gadget>
<output>670</output>
670 miles.   The total time taken= 7+8= 
<gadget id="calculator">7+8</gadget>
<output>15</output>
15hours.   Hence, the average speed=670/15= 44.6 mph.   Answer : 44.6 mph
<result>B</result>
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?