At a conference, the only events scheduled for the day...

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At a conference, the only events scheduled for the day are seminars and breaks. All seminars are the same length and are 10 times as long as each break. A break must be between two consecutive seminars. if the first seminar begins at 9:00 am and the third one ends at 11:40 am, how long will the conference last if there are a total of 6 seminars that day?

A. 5 hours and 15 minutes
B. 5 hours and 20 minutes
C. 5 hours and 25 minutes
D. 5 hours and 30 minutes
E. 5 hours and 35 minutes

The OA is C.

Experts, shouldn't the answer be 5 hours 20 mins?

Break = b
Seminar= 10b

9am to 11:40am = 160mins

3s+b=160
30b+b=160
b=160/31

6 seminar will take

6s+2b

=60b+2b

=62b

=62*160/31

=320

=5 hours 20 minutes.

I don't have clear this PS question. I appreciate if any expert explains it to me. Thank you so much.

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by ErikaPrepScholar » Wed Mar 14, 2018 9:27 am
Hey AAPL,

You're on the right track with creating these equations. However, it's important to note that the question tells us that breaks are scheduled between 2 consecutive seminars - this means that we should never have 2 seminars in a row without a break between them. So from 9am to 11:40, there should be 3 seminars and 2 breaks, and in total, there should be 6 seminars and 5 breaks.

This gives us
3s+2b=160

If s = 10b, then
30b+2b=160
32b=160
b=160/32

6 seminars will take
6s+5b
=60b+5b
=65b
=65*160/32
=325
=5 hours 25 minutes.
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by Scott@TargetTestPrep » Thu Mar 15, 2018 9:19 am
AAPL wrote:At a conference, the only events scheduled for the day are seminars and breaks. All seminars are the same length and are 10 times as long as each break. A break must be between two consecutive seminars. if the first seminar begins at 9:00 am and the third one ends at 11:40 am, how long will the conference last if there are a total of 6 seminars that day?

A. 5 hours and 15 minutes
B. 5 hours and 20 minutes
C. 5 hours and 25 minutes
D. 5 hours and 30 minutes
E. 5 hours and 35 minutes
We can let x = the length, in minutes, of a break; thus, 10x = the length, in minutes, of a seminar. Since the first seminar begins at 9:00 am and the third one ends at 11:40 am, the time elapsed is 2 hours 40 minutes, or 160 minutes. This means that the total length of 3 seminars and 2 breaks is 160 minutes. We can translate this into an equation:

3(10x) + 2x = 160

32x = 160

x = 5

So each break is 5 minutes long and each seminar is 5(10) = 50 minutes long. If a day has a total of 6 seminars, it will have 5 breaks and, thus, a day of 6 seminars and 5 breaks will last

6(50) + 5(5) = 325 minutes = 5 hours 25 minutes

Answer: C