Final answer:
Sallie-Mae and Johnnie-Wayne would take approximately 1.36 hours to complete house chores together when combining their individual work rates.
Step-by-step explanation:
The question asks how long it would take for Sallie-Mae and Johnnie-Wayne to do house chores together. To solve this, we must first determine each person's work rate, which is the fraction of the work they can complete in one hour. Sallie-Mae can complete the chores in 2.5 hours, so her work rate is 1/2.5 or 0.4 of the work per hour. Johnnie-Wayne can do the same chores in 3 hours, so his work rate is 1/3 or approximately 0.333 of the work per hour. To find out how long they would take to do the chores together, we add their work rates:
0.4 (Sallie-Mae's work rate) + 0.333 (Johnnie-Wayne's work rate) = 0.733 work per hour together.
To find the time taken to do one complete set of chores together, we divide one complete set of chores (1 work) by their combined work rate (0.733):
1 ÷ 0.733 = approximately 1.364 hours.
Therefore, rounded to two decimal places, Sallie-Mae and Johnnie-Wayne would take 1.36 hours to complete the house chores together.