It is currently 25 Sep 2020, 16:58

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

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

If Mason is now twice as old as Gunther was 10 years ago, an

Author Message
TAGS:
Retired Moderator
Joined: 07 Jun 2014
Posts: 4803
GRE 1: Q167 V156
WE: Business Development (Energy and Utilities)
Followers: 171

Kudos [?]: 2921 [0], given: 394

If Mason is now twice as old as Gunther was 10 years ago, an [#permalink]  14 Jun 2018, 14:22
Expert's post
00:00

Question Stats:

86% (01:23) correct 13% (01:38) wrong based on 29 sessions
If Mason is now twice as old as Gunther was 10 years ago, and G is Gunther’s current age in years, which of the following represents the sum of Mason and Gunther’s ages 4 years from now?

(A) $$\frac{3G}{2}+ 3$$
(B) 3G + 28
(C) 3G – 12
(D) 8 – G
(E)$$14 – \frac{3G}{2}$$
[Reveal] Spoiler: OA

_________________

Sandy
If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test

Active Member
Joined: 29 May 2018
Posts: 126
Followers: 0

Kudos [?]: 110 [1] , given: 4

Re: If Mason is now twice as old as Gunther was 10 years ago, an [#permalink]  15 Jun 2018, 08:08
1
KUDOS
sandy wrote:
If Mason is now twice as old as Gunther was 10 years ago, and G is Gunther’s current age in years, which of the following represents the sum of Mason and Gunther’s ages 4 years from now?

(A) $$\frac{3G}{2}+ 3$$
(B) 3G + 28
(C) 3G – 12
(D) 8 – G
(E)$$14 – \frac{3G}{2}$$

Correct me if my solution is wrong.

Mason is now twice as old as Gunther was 10 years ago => M = 2(G-10) = 2G-20

To find 'sum of Mason and Gunther’s ages 4 years from now', M+4 = 2G-20+4 =>2G-16 and G in another 4 years will G+4.

Sum of both 2G-16 + G + 4 => 3G - 12.

C.
Retired Moderator
Joined: 07 Jun 2014
Posts: 4803
GRE 1: Q167 V156
WE: Business Development (Energy and Utilities)
Followers: 171

Kudos [?]: 2921 [0], given: 394

Re: If Mason is now twice as old as Gunther was 10 years ago, an [#permalink]  05 Jul 2018, 03:04
Expert's post
Explanation

The sum of Mason and Gunther’s ages 4 years from now requires adding 4 to both ages.

The question asks for the following, the sum of Mason and Gunther’s ages 4 years from now:

$$(M + 4) + (G + 4) = ?$$

$$M + G + 8 = ?$$

Since Mason is twice as old as Gunther was 10 years ago, put (G – 10) in parentheses and build the second equation from there (the parentheses are crucial):

$$M = 2(G - 10)$$

$$M = 2G - 20$$

Note that the answer choices ask for the sum of the ages 4 years from now, in terms of G, so substitute for M (the variable you substitute for is the one that drops out).

Substituting from the second equation into the first:
$$(2G - 20) + G + 8 = ?$$

3G - 12 = ?

This matches choice C.

Alternatively, you could write the second equation, M = 2(G – 10), and then come up with two values that “work” in this equation for M and G. The easiest way to do this is to make up G, which will then tell you M. For instance, set G = 12 (use any number you want, as long as it’s over 10, since the
problem strongly implies that Gunther has been alive for more than 10 years):

$$M = 2(12 - 10)$$

$$M = 4$$

If Gunther is 12, then Mason is 4. In four years, they will be 16 and 8, respectively. Add these together to get 24.

Now, plug G = 12 into each answer choice to see which yields the correct answer (for this example), 24. Only choice (C) works.
_________________

Sandy
If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test

Re: If Mason is now twice as old as Gunther was 10 years ago, an   [#permalink] 05 Jul 2018, 03:04
Display posts from previous: Sort by