Answer:
48 minutes
Step-by-step explanation:
Given that;
Rosalinda can line the football field in 80 minutes
Reggie can line the football field in 120 minutes
Lets assume that if they work together, they will take T minutes to line the football field
Hence;
Thus in 1 minute, Rosalina can line 1/80 of the field where as Reggie can line 1/120 of the field
The sum of the two fractions will represent the size of the field that can be lined in 1 minute.
The reciprocal of the sum of the two fractions will represent the time taken for both Rosalinda and Reggie to line the field.
Answer ; It will take them 48 minutes for them to line the football field