A varies directly as the sum of the two quantities B and C. B in turn varies directly as x and C varies inversly as x.
When x=2, A=6 and when x=4 , A=9. Find the value of A when the value of x=16.
1)2.5 2)1 3)8.5 4)32.5
Answer [spoiler](4)[/spoiler]
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
Variations and Propotions - Difficult
This topic has expert replies
When x=2, A=6
eqn: Bx + C/x = 6
i.e: 2B + C/2 = 6 ....... I
when x=4 , A=9
eqn: Bx + C/x = 9
i.e.: 4B + C/4 = 9 ....... II
Solving I and II we get B = 2, C = 4
Now B = 2, C = 4 and x = 16
eqn: Bx + C/x
= 2(16) + 4/16
= 32 + 0.25
= 32.25
Closest is option D
Can you check if its correct?
eqn: Bx + C/x = 6
i.e: 2B + C/2 = 6 ....... I
when x=4 , A=9
eqn: Bx + C/x = 9
i.e.: 4B + C/4 = 9 ....... II
Solving I and II we get B = 2, C = 4
Now B = 2, C = 4 and x = 16
eqn: Bx + C/x
= 2(16) + 4/16
= 32 + 0.25
= 32.25
Closest is option D
Can you check if its correct?
-
gmatrant
- Master | Next Rank: 500 Posts
- Posts: 416
- Joined: Wed Oct 03, 2007 9:08 am
- Thanked: 10 times
- Followed by:1 members
You are right the answer is 32.25.. Sorry for the typoSuyog wrote:When x=2, A=6
eqn: Bx + C/x = 6
i.e: 2B + C/2 = 6 ....... I
when x=4 , A=9
eqn: Bx + C/x = 9
i.e.: 4B + C/4 = 9 ....... II
Solving I and II we get B = 2, C = 4
Now B = 2, C = 4 and x = 16
eqn: Bx + C/x
= 2(16) + 4/16
= 32 + 0.25
= 32.25
Closest is option D
Can you check if its correct?
