Answer: 350%
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Explanation:
1 hour = 60 minutes
2 hours = 120 minutes (multiply both sides by 2)
2 hrs + 20 min = 120 min + 20 min (add 20 min to both sides)
2 hrs, 20 min = 140 min
Juan studied for 140 min
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Ken studied for 2/3 of an hour, so he studied for (2/3)*60 = 120/3 = 40 min
We see that Juan studied more than Ken, so that must mean Juan's study time as a percentage of Ken's study time is over 100%
This is because
- 100% of 40 min = 1.00*40 = 40 min
- 200% of 40 min = 2.00*40 = 80 min
- 300% of 40 min = 3.00*40 = 120 min
and so on
We divide Juan's time by Ken's time to get: 140/40 = 3.5 = 350%
350% of Ken's study time was Juan's study time.
In other words, if we take 350% of the 40 min figure, then we get 3.5*40 = 140 which represents Juan's study time.
If your teacher asked the reverse of this, and instead asked "what percent of Juan's study time was Ken's?", then the answer would be 40/140 = 0.2857 = 28.57% approximately.
