BTGmoderatorLU wrote:If the average of 7 numbers is 72, how many of the numbers are equal to 72?

(1) Of the seven numbers, six are odd integers, and the average of those integers is 72.
(2) At least one of the numbers is equal to 72.

The OA is A.

Please, can someone assist me with this DS question? It would be great if someone explains how can I solve this question using the first statement. Thanks!

Given: The average of 7 numbers is 72.

To find: How many of the numbers are equal to 72?

Let's take each statement one by one.

(1) Of the seven numbers, six are odd integers, and the average of those integers is 72.

Since 72 is an even number, and six of the seven numbers are odd, we have to determine whether the 7th number is 72.

Since the average of 7 numbers, as well as the 6 numbers, is 72, it implies that the 7th number itself is 72, otherwise, it is not possible. Thus, only one number is 72. Sufficient.

(2) At least one of the numbers is equal to 72.

Certainly insufficient.

The correct answer: A

Hope this helps!

-Jay
_________________
Manhattan Review Test Prep

Locations: Manhattan Review Begumpet | Free GRE Practice Test | GRE Prep Hyderabad | Dilsukhnagar GRE Coaching | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.