Hello Sassanah,
Let's solve this problem using the concept of the work rate.
Sue's work rate is 1 job per 5 hours, and Felipe's work rate is 1 job per 7 hours.
When they work together, their work rates are combined. So, the combined work rate is the sum of their individual work rates:
Sue's work rate + Felipe's work rate = 1/5 + 1/7
To add these fractions, we need to find a common denominator, which is 35. So, we get:
7/35 + 5/35 = 12/35
This means that together, they complete 12/35 of the job per hour.
To find out how long it will take them to complete the job together, we can divide the total work (1 job) by their combined work rate:
Time taken = Total work / Combined work rate
Time taken = 1 / (12/35)
Time taken = 35/12
Now, we need to convert 35/12 to hours and minutes:
When 35 is divided by 12, it gives 2 with a remainder of 11.
35/12 = 2 11/12
This is 2 hours and 11/12 of an hour which is 55 minutes.
So, it will take Sue and Felipe approximately 2 hours and 55 minutes to fill the order together.