Explanation:
It is given that,
A rescue company determined that 90 out of 100 calls rescue company determined that 90 out of 100 calls. We need to find the fraction of their calls that were true emergencies.
Fractions can be written as true value on the denominator and the part of it on the numerator.
The required value is :

So, (9/10) describes the fraction of their calls that were true emergencies.