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

Redeem

If the product of 5 different positive integers is less than

Expert replies
by Max@Math Revolution » Wed Jun 20, 2018 12:35 am

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty

[GMAT math practice question]

If the product of 5 different positive integers is less than 200, what is the greatest possible value for the largest of these 5 integers?

A. 3
B. 6
C. 7
D. 8
E. 9
Join the discussion
Source: — Problem Solving |

by GMATGuruNY » Wed Jun 20, 2018 1:58 am
Max@Math Revolution wrote:[GMAT math practice question]

If the product of 5 different positive integers is less than 200, what is the greatest possible value for the largest of these 5 integers?

A. 3
B. 6
C. 7
D. 8
E. 9
To MAXIMIZE the largest integer, MINIMIZE the other four integers.
Since the integers must be positive and distinct, the smallest possible option for the other four integers is as follows:
1*2*3*4 = 24.
We can PLUG IN THE ANSWERS, which represent the value of the largest integer.
Of the five answer choices -- 3, 6, 7, 8, 9 -- the largest that can be multiplied by 24 to yield a product less than 200 is 8:
24*8 = 192.

The correct answer is D.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Join the discussion

by Jeff@TargetTestPrep » Thu Jun 21, 2018 4:15 pm
Max@Math Revolution wrote:
If the product of 5 different positive integers is less than 200, what is the greatest possible value for the largest of these 5 integers?

A. 3
B. 6
C. 7
D. 8
E. 9
To maximize the largest of the 5 integers, we minimize the values of the smallest 4 integers. Since they are positive and are different from each other, they must be 1, 2, 3, and 4. The product of the first four integers is 1 x 2 x 3 x 4 = 24.

The largest integer that could multiply 24 and produce a product that is less than 200 is 8, since 24 x 8 = 192.

Answer: D

Jeffrey Miller
Head of GMAT Instruction
[email protected]

Image

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

by Max@Math Revolution » Thu Jun 21, 2018 11:33 pm
=>
The greatest possible value of the largest of the integers occurs when the other integers are as small as possible. In other words, the other four integers should be 1,2,3, and 4.

We try different values for the fifth integer:
1*2*3*4*5 = 120
1*2*3*4*6 = 144
1*2*3*4*7 = 168
1*2*3*4*8 = 192
1*2*3*4*9 = 216

The largest product that is less than 200 occurs when the fifth integer is 8.
Thus, the greatest possible value of the largest integer is 8.

Therefore, the answer is D.
Answer: D
Join the discussion