Question

A cheetah was chasing and antelope which is 700m away. How many minutes will it take the cheetah, which is running at a constant speed of 110km/h to reach the antelope that is running at a constant speed of 75km/h?

Answer 1

1 min 12 sec

Explanation:

Cheetah has to reach the antelope with its relative speed `(115-75)=35` km/h.
Time = distance/speed = `0.7/35` km/h=`1/50`h = 1.2 min = 1min 2sec..

Answer 2

Time `t=0.02` hours`=1.2` minutes

Explanation:

time (Cheetah)=time(Antelope)

`t_c=t_a`

`d_c/v_c=d_a/v_a`

`(0.7+x)/110=x/75`

`75(0.7+x)=110x`

`75(0.7+x)/5=(110x)/5`

`15(0.7+x)=22x`

`15(0.7)+15x=22x`

`7x=15(0.7)`

`x=1.5 km`

Solve time t:

`t=d_a/v_a=1.5/75=0.02 " "`hour

`t=0.02 * 60 =1.2` minutes

God bless....I hope the explanation is useful.