Chris tosses all his spare change

[saxenashobhit]

Chris tosses all his spare change into a jar on his refrigerator. Once the jar is full, Chris counts out the coins and finds that he has only pennies, nickels, and dimes in the exact ratio of 1:4:8. How many nickels does he have?

1) There are exactly 650 coins in the jar.
2) The ratio of dimes to pennies is 8:1.

Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.

Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.

Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.

EITHER statement BY ITSELF is sufficient to answer the question.

Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

Kaplan question 8 - https://www.scribd.com/doc/58999877/GMAT ... et-6-Quant

[Ian Stewart]

Chris tosses all his spare change into a jar on his refrigerator. Once the jar is full, Chris counts out the coins and finds that he has only pennies, nickels, and dimes in the exact ratio of 1:4:8. How many nickels does he have?

1) There are exactly 650 coins in the jar.
2) The ratio of dimes to pennies is 8:1.

You know the ratio of coins of each type, so if you know the total number of coins, you can then find the number of coins of each type, so statement 1 has to be sufficient. If you actually needed to find the answer (it's DS, so you don't, but if it were PS), if the ratio of pennies to nickels to dimes is 1 to 4 to 8, then 1/(1+4+8) = 1/13 of all coins are pennies, 4/(1+4+8) = 4/13 of all coins are nickels, and 8/(1+4+8) = 8/13 of all coins are dimes. So the number of nickels would be (4/13)(650) = 200.

Statement 2 just rephrases information provided in the question, so isn't helpful, and the answer is A.

[mirantdon]

+1 for A.
Ian do we get such questions on the Gmat . ?
where there is some redundant data in one of the options ?

[Ian Stewart]

+1 for A.
Ian do we get such questions on the Gmat . ?
where there is some redundant data in one of the options ?

Yes, on occasion insufficient Statements will sometimes simply rephrase information in the stem, though it's rarely as obvious as in the question above.