Answer:
5 1/7 hours
Step-by-step explanation:
We're looking to calculate TIME. In this situation the proper expression is:
6 letters
time = -----------------------------------------------------------
2 letters / 4 hours + 2 letters / 6 hours
We can divide numerator and denominator both by "2 letters" to simplify the problem:
3 3 hours 3 hours
time = ----------------- hours, or ------------------ = -----------------
1/4 + 1/3 3/12 + 4/12 7/12
Invert the divisor 7/12, and then multiply: (3 hours) (12/7) = 36/7 hours, or
5 1/7 hours
It will take these two guys 5 1/7 hours, working together, to type these 6 letters.
