PLEASE help me? okay well it's math so yeah...?

Question

kid ran 2 laps in 99 sec. one was 8.0m/s one was 8.5m/s, how long did it take him to run each lap?

Answer 1

The basic formula in these cases is D = RT. I've used it all my life, it's very helpful. In any case, the Distance is the same since he's running laps.
The Rates are given as 8m/s & 8.5m/s with total of 99 sec.
You are looking for Time, T1 and T2.

Since D = RT, R = D/T and
8 = D/T1
8.5 = D/T2
T1 + T2 = 99
8 = D/(99-T2)
792 - 8T2 = D
8.5T2 = D
792 - 8T2 = 8.5T2
792 = 8.5T2 + 8T2
792 = 16.5T2
48 = T2 and since T1 = 99 - T2:
51 = T1
Your answers are 48 seconds and 51 seconds

Answer 2

He ran one lap in 51 seconds and the other lap in 48 seconds.

(time) * (speed) = distance; the distance in both cases is the same (one lap). Let t and T be the lap times.
So 8 t = 8.5 T where t + T = 99
Then t = 99 - T, and 8.5 T = 8 ( 99 - T) = 792 - 8 T.
Thus 16.5 T = 792, or T = 792 / 16.5 = 48, and t = 99 - 48 = 51

(51 s) * (8.0 m/s) = 408 m
(48 s) * (8.5 m/s) = 408 m
51 s + 48 s = 99 s

Answer 3

Let the time taken be t1 and t2 seconds respectively.
We know that the more the speed,the less the time tken,in mathematical language ,we say that time is invrsely proportional to speed.
Therefore t1;t2=8.5:8=85:80=17:16
the sum of the ratios = 17+16=33
Total time tken=99 seconds (given)
Therefore,t1=99X(17/33)=51 seconds ,and
t2=99X(16/33)=48 seconds
Therefore,he tool 51 and 48 seconds respectively to run each lap