BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

A biotechnologist started an automated half-hourly recording of the conditions of a cell culture at 9 AM on 13 January 2

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 1622
Joined: Thu Mar 01, 2018 7:22 am
Followed by:2 members

A biotechnologist started an automated half-hourly recording of the conditions of a cell culture at 9 AM on 13 January 2

by Gmat_mission » Thu Dec 17, 2020 1:06 pm

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

QS079.png
A biotechnologist started an automated half-hourly recording of the conditions of a cell culture at 9 AM on 13 January 2015. The dial on the recording device moved clockwise through one interval (for example, from A to B) after every 10 recordings. If the dial was at point A at 9 AM on 13 January 2015, what was the position of the dial, time, and date respectively when the 420th recording of the cell culture was taken?


A. B, 3 AM, 21 January 2015

B. B, 6 AM, 21 January 2015

C. C, 6 PM, 21 January 2015

D. C, 3 AM, 22 January 2015

E. B, 6 AM, 22 January 2015

Answer: D

Source: e-GMAT
Top
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8086
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members

Re: A biotechnologist started an automated half-hourly recording of the conditions of a cell culture at 9 AM on 13 Janua

by Scott@TargetTestPrep » Wed Dec 23, 2020 4:07 pm
Gmat_mission wrote: ↑
Thu Dec 17, 2020 1:06 pm
 QS079.png

A biotechnologist started an automated half-hourly recording of the conditions of a cell culture at 9 AM on 13 January 2015. The dial on the recording device moved clockwise through one interval (for example, from A to B) after every 10 recordings. If the dial was at point A at 9 AM on 13 January 2015, what was the position of the dial, time, and date respectively when the 420th recording of the cell culture was taken?


A. B, 3 AM, 21 January 2015

B. B, 6 AM, 21 January 2015

C. C, 6 PM, 21 January 2015

D. C, 3 AM, 22 January 2015

E. B, 6 AM, 22 January 2015

Answer: D

Solution:

Since 420 recordings were taken and since recordings are taken every 30 minutes, the 420th reading is taken 210 hours after 9 AM on January 13th. Notice that 210 hours = 8 days 18 hours. Notice also that 8 days from 9 AM, January 13th is 9 AM, January 21st. Adding another 18 hours, we arrive at 3 AM, January 22nd. There is only one answer choice with this date and time, so the correct answer is D.

Answer: D

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Top
Post new topic Post Reply
• Page 1 of 1