Kevin buys beer in bottles and cans. He pays $1.00 for each can of beer and $1.50 for each bottle...

[BTGmoderatorLU]

Source: Princeton Review

Kevin buys beer in bottles and cans. He pays $1.00 for each can of beer and $1.50 for each bottle of beer. If he buys a total of 15 bottles and cans of beer, how many bottles of beer did he buy?

1) Kevin spent a total of $18.00 on beer.
2) Kevin bought 3 more cans of beer than bottles of beer.

The OA is D

[Brent@GMATPrepNow]

Source: Princeton Review

Kevin buys beer in bottles and cans. He pays $1.00 for each can of beer and $1.50 for each bottle of beer. If he buys a total of 15 bottles and cans of beer, how many bottles of beer did he buy?

1) Kevin spent a total of $18.00 on beer.
2) Kevin bought 3 more cans of beer than bottles of beer.

The OA is D

Target question: How many bottles of beer did Kevin buy?

Given: Kevin pays $1.00 for each can of beer and $1.50 for each bottle of beer. Kevin buys a total of 15 bottles and cans of beer
Let C = the NUMBER of Cans that Kevin bought
Let B = the NUMBER of Bottles that Kevin bought
So, we can write: C + B = 15

Statement 1: Kevin spent a total of $18.00 on beer
The COST of C cans = ($1.00)C = 1C
The COST of B bottles = ($1.50)B = 1.5B
So, we can write: 1C + 1.5B = 18.00

When we combine this equation with the equation we created from the given information, we have:
C + B = 15
1C + 1.5B = 18.00

Since we COULD solve this system for C and B, we COULD determine the number of bottles of beer that Kevin bought.
(of course, we won't solve the system, since that would be a waste of our valuable time!)
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: Kevin bought 3 more cans of beer than bottles of beer
We can write: C = B + 3

When we combine this equation with the equation we created from the given information, we have:
C + B = 15
C = B + 3

Since we COULD solve this system for C and B, we COULD determine the number of bottles of beer that Kevin bought.
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer: D

Cheers,
Brent

[deloitte247]

Given that;
Kelvin buys beer in bottles and cans .
He pays $1.00 for each can of beer.
He pays $1.50 for each bottle of beer.
Total no of bottles +total no of cans =15
Target question
How many bottles of beer did he buy?
Statement 1
Kelvin spent $18.00 on beer
Let total no of bottles = b and total no of cans =c
from the question stem
b+c=15........eqn 1
1 bottle costs $1.5
and 1 can cost $1.00
1.5b+1c=18................eqn (ii)
from eqn i, c=15-b-------eqn iii
Substituting eqn iii in eqn ii
1.5b+1(15-b)=18
1.5b+15-b=18 $$\frac{0.5b}{0.5}=\frac{18-15}{0.5}=\frac{3}{0.5}=6$$

Statement 1 is INSUFFICIENT.
Statement 2
Kelvin bought 3 more cans of beer than bottles of beer
Let total no of bottles = b and no of cans = c
c=b+3
from the question stem b+c=15 where c=b+3
b+b+3=15
2b+3=15
$$\frac{2b}{2}=\frac{15-3}{2}=\frac{12}{2}=6$$
Statement 2 is also SUFFICIENT. Since each statement alone is SUFFICIENT.
$$Answer\ is\ Option\ D$$