Question

a car covers first 50 kilometre of its journey at the speed of 75 km per hour next 90 kilometre at the speed of 80 kilometre per hour and the rest of its 240 km journey at the speed of 120 km per hour find the time taken to complete its journey also find its a average speed

Answer 1

hello users....
given that a car covers first 50 kilometre of its journey at the speed of 75 km per hour next 90 kilometre at the speed of 80 kilometre per hour and the rest of its 240 km journey at the speed of 120 km per hour
we have to find the time taken to complete its journey also find its a average speed
solution:-we know thatspeed = distance / time => time = distance / speed 
now ,50 kilometre of its journey at the speed of 75 km per hour => time taken = 50/75 = 2/3 h 
and next 90 kilometre at the speed of 80 kilometre per hour => time taken = 90/80 = 9/8 h
and the rest of distance of 240 km journey 100 km journey at the speed of 120 km per hour => time taken= 100/120 = 5/6 h 
here the total time taken for his journey = 2/3 + 9/8 +5/6 = (32+ 54+40)/48(taking LCM)
=> 126/48= 2.625 h or 2h 37m 30sec
and average speed = total distance covered / total time taken 
here total distance = 50+90+100 = 240 km & total time taken = 2.625 h 
so average speed = 240/2.625 = 91.42 km/h answer 
⭐⭐ hope it helps ⭐⭐

Answer 2

Answer:

Step-by-step explanation:

i forgot