Question

Sammy had 30 minutes to do a three problem quiz. She spent 10 1/3 minutes on problem 1 and 5 4/5 minutes on problem 2. How much time did she have time for problem 3? Write your answer as a mixed number.

Answer 1

The time spent on problem 3 is
`13(13)/(15) \text{ minutes }`

Solution:

Given that Sammy had 30 minutes to do a three problem quiz

To find: Remaining time left for problem 3

From given question,

Total time = 30 minutes

Time spent on problem 1 =
`10(1)/(3) \text{ minutes }`

`\rightarrow 10(1)/(3) = (3 * 10 + 1)/(3) = (31)/(3) \text{ minutes }`

Time spent on problem 2 =
`5(4)/(5) \text{ minutes }`

`\rightarrow 5(4)/(5) = (5 * 5 + 4)/(5) = (29)/(5) \text{ minutes }`

Therefore,

Time spent on problem 3 = total time - (time on problem 1 + time on problem 2)

`\text{ Time spent on problem 3 } = 30 - ((31)/(3) + (29)/(5))\\\\\rightarrow 30 - (31 * 5 + 29 * 3)/(3 * 5)\\\\\rightarrow 30 - (242)/(15)\\\\\rightarrow (30 * 15 - 242)/(15)\\\\\rightarrow (208)/(15) = 13(13)/(15)`

Thus time spent on problem 3 is
`13(13)/(15) \text{ minutes }`