The afternoon before a popular amusement park opens for the season, Sh

Question

The afternoon before a popular amusement park opens for the season, Shirley has a pass that will let her ride each ride continuously without waiting in line. For each of the four most popular rides, the ride will run for an allotted time, then stop to change passengers (in negligible time) and start again. The Sea Serpent runs every 15 minutes starting at 10am. The Wild Mouse runs every 30 minutes starting at 11am. The Raptor runs every 40 minutes starting at noon. And the Mantis runs every 45 minutes starting at 11am. Each ride runs continuously and stops only to let its passengers off and immediately begin again. If Shirley is able to get on her first ride starting at 2:00pm and wants to ride all four rides, but needs 10 minutes between rides to move from one to the next, what is the earliest time she could finish riding all four rides?

A. 4:15pm
B. 4:30pm
C. 4:45pm
D. 5:00pm
E. 5:15pm

Kudos for a correct solution.

A. 4:15pm
B. 4:30pm
C. 4:45pm
D. 5:00pm
E. 5:15pm

Kudos for a correct  solution .

KarishmaB · Accepted Answer

It does require you to find the ride timing pattern but thereafter, it takes a few secs only. She enters at 2 so jot down the timings from 2 onwards:

SS - 2:00, 2:15, 2:30, 2:45, 3:00, 3:15 (ignore 10, 10:15, 10:30 etc)
WM -  2:00, 2:30 , 3:00, 3:30, 4:00, 4:30 (ignore 11, 11:30...etc)
Rap - 2:00,  2:40, 3:20 , 4:00, 4:40, (ignore 12, 12:40, 1:20 though you need to review them in mind to know at what time the first ride runs at or after 2)
Man - 2:00, 2:45,  3:30, 4:15 , 5:00 (ignore 11, 11:45, 12:30, 1:15)

Now look for exact 10 min intervals between the rides to take minimum time. Look at the highlighted spots: WM from 2 to 2:30, Rap from 2:40 to 3:20 and Man from 3:30 to 4:15. Now you are left with SS which you can start at 4:30 (15 min break) and get done by 4:45. Note that you took 5 mins more than the minimum time you could have taken riding each ride with 10 mins breaks. 
Looking at the options, you see that 4:45 is there and the earlier option is 4:30. There is no way you could have been done by 4:30 since you took only 5 mins more than the minimum. Hence (C) must be the answer.

Celestial09 · Answer

Hi,
IMO it should be C that is 4:45pm
Started at 2pm with the widl mouse , ended at 2:30pm. took 10 mins break = 2:40pm
@ 2:40pm she rode the raptor which ended at 3:20pm , took 10 mins break = 3:30pm
@3:30pm she rode the mantis which ended at 4:15pm, took 10 mins break = 4:25pm
@ 4:30pm only she could ride sea serpent which will end at 4:45pm.

Hence C

Regards
Celestial.

Kudos if it a correct solution

shriramvelamuri · Answer

Hi,

C for me as below.

First the 45 mins ride, then 30 min, ride, 40 min ride, and finally 15 min ride.

adityadon · Answer

solved it ... answer is C .. but took 5 mints

any shortcut on this ?

Lucky2783 · Answer

First thing to note is that all the rides will be in ready to board state at 2PM . how ? 
sea serpent @10am + 15*4*4mins = 2PM
Wild mouse @11am + 30*2*3mins = 2PM
Raptor @12PM + 40*3 = 2PM
Manits @11AM + 45*4= 2PM

now i see these four numbers and quickly identified that we have to start with wild mouse as i will get 30,40,45 all in series with 10min gap.
 15, 30 , 40 , 45

30(wild mouse) +10(min wait) =40(raptor 40*1)
30+10(wait)+40+10(wait) =90(Mantis 45*2) 
30+10(wait)+40+10(wait)+45+10(wait)=145
as 15*10=150 so she has to wait for another 5 mins so finally the the total time taken is

30+10(wait)+40+10(wait)+45+10(wait)+5(min)+15 = 165mins .

2PM + 165mins = 4PM + 45Mins

answer C

Bunuel · Answer

VERITAS PREP OFFICIAL SOLUTION:

The good news is that all four rides will begin exactly at 2pm, so you have a common starting point to begin mapping out her afternoon. Also noteworthy is that only one ride (the 40-minute Raptor) has a duration that’s not a multiple of 15, meaning that fitting in the Raptor will be interesting. One way to minimize the amount of time, then, is to look at which other numbers (15, 30, and 45) will, with a 10-minute break after, end in a 40 or 20. That allows you to start with the 30-minute ride from 2pm to 2:30, then take the mandatory 10 minute break, and immediately get on the 2:40 ride for the 40-minute event. That takes you to 3:20, and a 10-minute break gets you to exactly 3:30, when any of the remaining two (the 45-minute ride and the 15-minute ride) will be leaving. If you then take the 45-minute ride, that will take you to 4:15, at which point you need one more 10-minute break to get to 4:25. Now is your first “deadweight” piece of time, a 5-minute rest until 4:30 when you can take the 15-minute ride and be done at 4:45.

With a time of 4:45 already achieved, D and E are eliminated. And since there were only 5 “wasted” (not riding, not walking from ride to ride in a 10-minute break) minutes, there clearly isn’t a way to shave down to 4:30. Therefore you can confidently pick C, the correct answer.

Bambi2021 · Answer

I was a question mark for 10 min and just couldn't see what I didn't understand. I guess my knowledge of the world was stopping me from realising that the rides wouldnt stop for up to 45 mins. This girl must have been really dizzy the evening after. Before realising this, I got a time of 15:30 with an average riding time of 5 min.

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The afternoon before a popular amusement park opens for the season, Sh

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