BTGmoderatorDC wrote: ↑

Thu Jun 16, 2022 6:41 am

Ten years ago, Dorothy deposited a certain amount of money in Account A at a 3% simple annual interest rate. At the same time, Marla deposited another amount in Account B at a 4% simple annual interest rate. If there were no withdrawals or deposits during the 10 years since the deposits, is the current interest in A greater than that in B?

(1) The amount invested in Account A was $1,000 more than the amount invested in Account B.

(2) The investment in Account A obtained interest of $300 last year.


OA C

Source: EMPOWERgmat

Interest (D) \(= \dfrac{D\cdot 3\cdot 10}{100}\)

Interest (M) \(= \dfrac{M\cdot 4\cdot 10}{100}\)

Statements:

(1) The amount invested in Account A was $1,000 more than the amount invested in Account B.
\(D = M + 1000\). Insufficient \(\Large{\color{red}\chi}\)

(2) The investment in Account A obtained interest of $300 last year.
\(\dfrac{3D}{100} = 300\)
\(D = 10000\)
Nothing about M. Insufficient \(\Large{\color{red}\chi}\)

Combining, we get
\(D = M +1000 \,\&\, D = 10000\). Sufficient \(\Large{\color{green}\checkmark}\)

Hence, C