Joan spent $10 to buy at least one piece each of apples and oranges

[BTGModeratorVI]

Joan spent $10 to buy at least one piece each of apples and oranges at a store where each apple cost $2 and each orange cost $1. How many apples did she buy?

(1) She spent more than $6 on buying oranges

(2) She spent less than $10 on buying oranges

Answer: A
Source: e-GMAT

[Brent@GMATPrepNow]

Joan spent $10 to buy at least one piece each of apples and oranges at a store where each apple cost $2 and each orange cost $1. How many apples did she buy?

(1) She spent more than $6 on buying oranges

(2) She spent less than $10 on buying oranges

Answer: A
Source: e-GMAT

Target question: How many apples did Joan buy?

Given: Joan spent $10 to buy at least one piece each of apples and oranges at a store where each apple cost $2 and each orange cost $1.
Since there are only a handful of possible outcomes, we might benefit from quickly listing them:
i) Joan buys 1 apple (for $2) and 8 oranges (for $8)
ii) Joan buys 2 apples (for $4) and 6 oranges (for $6)
iii) Joan buys 3 apples (for $6) and 4 oranges (for $4)
iv) Joan buys 4 apple (for $8) and 2 oranges (for $2)

Statement 1: She spent more than $6 on buying oranges
When we check our list of possible outcomes, we see that only one outcome (case i) satisfies statement 1.
So, it MUST be the case that Joan bought 4 apples
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: She spent less than $10 on buying oranges
When we check our list of possible outcomes, we see that ALL 4 outcomes satisfy statement 2.
So, it's possible that Joan bought 1 apple, 2 apples, 3 apples OR 4 apples
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Answer: A

Cheers,
Brent