Step-by-step explanation:
the car went 25 meters in 1 second.
that creates this ratio 25 m/s or
formally fully correct 25/1 m/s.
to get the speed in km/h we need to bring the denominator of that ratio from 1 second to 1 hour.
we do that by multiplying it by 3600, as there are 3600 second in 1 hour.
to keep the overall value of the ratio we need to multiply also the numerator with the same factor.
so,
25/1 × 3600/3600 = (25×3600)/3600 =
= 90000 meters /1 hour
how many km (kilometers) are 90000 meters ?
1 km = 1000 m
so,
90000 m = 90000/1000 km = 90 km
therefore, or full answer is
the car's speed was 90 km/h.
