Answer:
Pat t2 = 40 hrs
Explanation:
Given:-
- Fred can paint a house in t1 = 10 hours.
- Pat can paint a house in t2 hours.
- pat and Fred can paint a house in T = 8 hours.
Find:-
Which equation, when solved will produce the number of hours need for pat to paint the house alone
Solution:-
- The number of people working on a particular activity " painting a house " is inversely proportional to time taken to complete the activity. tn = T. The relation for individual time taken ti to complete an activity.
Sum ( 1 / ti ) = 1 / T
Where, ti = The individual time for (ith) person
T = The total time taken to complete the time by i = n number of people.
- For n = 2,
1/t1 + 1/t2 = 1/T
1/10 + 1/t2 = 1/8
1 / t2 = 0.025
t2 = 40 hrs
- It takes Pat t2 = 40 hrs to complete painting the house.