Question

Tina took 2⅓ hours to travel 4 by 9 of the distance between Town A and Town B at an average speed of 72km/h what was Tina's average speed if she took 4 hours 12 minutes to tavel from Town A to Town B.​

Answer 1

Answer:

Tina took 7/3 hours to travel 4/9 distance between Town A and town b.

speed= 72km/h

now, she took 4 hours 12 minutes to travel from Town A and Town B.

find the speed ?

let the distance = 4/9x

so, distance= speed × time

4/9x= 72× 7/3

4/9x= 24×7/1

4/9x= 168/1

4x×1=9×168

4x=1512

x= 1512÷4x

x= 378 km

then now time = 4hours + 12 minutes

so, 1 hours = 60 minutes

4 hours= 4× 60+12=240+12=252 minutes

then, 1 minutes= 1/60 hours= 252÷60 = 21/5 hours

now, speed = distance× time

= 378×5/21

= 90km/h.r

hence, when Tina took 4 hours 12 minutes to complete distance town a and town b then speed is 90 km/ h.r

Answer 2

let the total distance be x

tina took 7/3 hours to travel 4/9x distance at speed of 72 km/hr

so

distance = speed x time

4/9x = 7/3×72

x= 378 km

now new time is 4 hrs + 12 mins

4 + 12/60 hours

time = 21/5 hours

speed = distance/time

=378×5/21

=90 km/hr