Last visit was: 27 Apr 2026, 16:22 It is currently 27 Apr 2026, 16:22
Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 27 Apr 2026
Posts: 109,929
Own Kudos:
811,617
 [2]
Given Kudos: 105,914
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,929
Kudos: 811,617
 [2]
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
User avatar
GMATinsight
User avatar
Major Poster
Joined: 08 Jul 2010
Last visit: 26 Apr 2026
Posts: 6,977
Own Kudos:
Given Kudos: 128
Status:GMAT/GRE Tutor l Admission Consultant l On-Demand Course creator
Location: India
GMAT: QUANT+DI EXPERT
Schools: IIM (A) ISB '24
GMAT 1: 750 Q51 V41
WE:Education (Education)
Products:
Expert
Expert reply
Schools: IIM (A) ISB '24
GMAT 1: 750 Q51 V41
Posts: 6,977
Kudos: 16,927
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Archit3110
User avatar
Major Poster
Joined: 18 Aug 2017
Last visit: 27 Apr 2026
Posts: 8,633
Own Kudos:
5,191
 [2]
Given Kudos: 243
Status:You learn more from failure than from success.
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1: 545 Q79 V79 DI73
GMAT Focus 2: 645 Q83 V82 DI81
GPA: 4
WE:Marketing (Energy)
Products:
GMAT Focus 2: 645 Q83 V82 DI81
Posts: 8,633
Kudos: 5,191
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
rohitz98
Joined: 15 Mar 2025
Last visit: 31 Dec 2025
Posts: 89
Own Kudos:
65
 [1]
Given Kudos: 16
Location: India
GMAT Focus 1: 725 Q81 V88 DI89
GMAT 1: 720 Q49 V60
GMAT Focus 1: 725 Q81 V88 DI89
GMAT 1: 720 Q49 V60
Posts: 89
Kudos: 65
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Given it takes x hrs for A to produce bolts and 2x/5 hrs for A&B to produce same no. of bolts
Let 'b' be number of hrs for B to produce same no. of bolts
Hence

1/x + 1/b = 5/2x

Solving be get b = 2x/3 Option C
User avatar
Dereno
Joined: 22 May 2020
Last visit: 27 Apr 2026
Posts: 1,398
Own Kudos:
1,374
 [1]
Given Kudos: 425
Products:
Posts: 1,398
Kudos: 1,374
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Machine A takes x hours to produce a batch of bolts. It takes \(\frac{2x}{5}\) hours for machine A and B working simultaneously to produce the same batch of bolts. In terms of \(x\), how many hours would it take machine B to produce the same batch of bolts working at its individual rate?

A) \(\frac{ x}{5}\)

B) \(\frac{x}{4}\)

C) \(\frac{2x}{3}\)

D) \(\frac{3x}{5}\)

E) \(\frac{x}{2}\)

­
Let machine A take x hours to produce a batch of bolts.

Let machines A and B together produce a batch of bolts in 2x/5 hours.

Machine B working alone produces ?

1/x + 1/B = 1/(2x/5)

1/B = 5/2x - 1/x

1/B = 3/2x

The time taken by B is 2x/3 hours.
User avatar
Ayeka
Joined: 26 May 2024
Last visit: 27 Apr 2026
Posts: 528
Own Kudos:
402
 [1]
Given Kudos: 158
Location: India
Schools: ISB
GMAT Focus 1: 645 Q82 V83 DI80
GPA: 4.2
Schools: ISB
GMAT Focus 1: 645 Q82 V83 DI80
Posts: 528
Kudos: 402
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Machine A takes x hours to produce a batch of bolts. It takes 2x/5 hours for machine A and B working simultaneously to produce the same batch of bolts. In terms of x, how many hours would it take machine B to produce the same batch of bolts working at its individual rate?

Let, machine B takes b hours to produce same batch of bolts individually.
(1/x)+1/b)= 1/(2x/5)
(1/b)= (5/2x)-(1/x)= (5-2/2x) = 3/2x
b= 2x/3

Answer: C
User avatar
HarshavardhanR
Joined: 16 Mar 2023
Last visit: 27 Apr 2026
Posts: 495
Own Kudos:
Given Kudos: 68
Status:Independent GMAT Tutor
Affiliations: Ex - Director, Subject Matter Expertise at e-GMAT
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 495
Kudos: 578
Kudos
Add Kudos
Bookmarks
Bookmark this Post


Harsha
Attachment:
GMAT-Club-Forum-2xk1t5vm.png
GMAT-Club-Forum-2xk1t5vm.png [ 149.78 KiB | Viewed 936 times ]
avatar
ManifestDreamMBA
Joined: 17 Sep 2024
Last visit: 21 Feb 2026
Posts: 1,387
Own Kudos:
Given Kudos: 243
Posts: 1,387
Kudos: 898
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Direct formula: Combined time = T1*T2/(T1+T2)

Let time taken by b be y

\(\frac{2x}{5}\) = \(\frac{xy}{(x+y)}\)
\(\frac{2}{5}\) = \(\frac{y}{(x+y)}\)
2x+2y = 5y
2x = 3y
y = \(\frac{2x}{3}\)

Bunuel
Machine A takes x hours to produce a batch of bolts. It takes \(\frac{2x}{5}\) hours for machine A and B working simultaneously to produce the same batch of bolts. In terms of \(x\), how many hours would it take machine B to produce the same batch of bolts working at its individual rate?

A) \(\frac{ x}{5}\)

B) \(\frac{x}{4}\)

C) \(\frac{2x}{3}\)

D) \(\frac{3x}{5}\)

E) \(\frac{x}{2}\)

­
Moderators:
Math Expert
109929 posts
Tuck School Moderator
852 posts