Answer :
- It will take 5 hours for Rachel to catch up with Nick.
Explaination :
Here we are given with two equations,
- f = 7h + 20 (Equation No 1)
- f = 10h + 5 Equation No 2)
So in order to calculate the number of hours (h). We would simply substitute the value of f in first equation. (i.e., keeping them equal)
>> 7h + 20 = 10h + 5
>> 10h - 7h = 20 - 5
>> 3h = 15
>> h = 15 / 3
>> h = 5
