RyanDe680
Robin split a total of $24,000 between 2 investments, X and Y. If investment Y earns 7% simple annual interest, how much of that total did Robin put into investment Y?
(1) Each investment earns the same dollar amount of the interest annually.
(2) Investment X earns 5 percent simple annual interest.
Statement 1:Test one case that also satisfies Statement 2.
Case 1: X = 5% and Y = 7%
For 5% interest and 7% percent interest to yield the same dollar amount,
$7 must be invested at 5% interest for every $5 invested at 7% interest:
X --> $7(0.05) = $0.35.
Y --> $5(0.07) = $0.35.
Thus:
\(\frac{X}{Y} = \frac{$7}{$5}\), implying that \(\frac{5}{12}\) of the $24,000 must be invested in Y:
\(\frac{5}{12} * 24,000 = 10,000\)
Test one case that does NOT also satisfy Statement 2.
Case 2: X = 3% and Y = 7%
For 3% interest and 7% percent interest to yield the same dollar amount,
$7 must be invested at 3% interest for every $3 invested at 7% interest:
X --> $7(0.03) = $0.21.
Y --> $3(0.07) = $0.21.
Thus:
\(\frac{X}{Y} = \frac{$7}{$3}\), implying that \(\frac{3}{10}\) of the $24,000 must be invested in Y:
\(\frac{3}{10}* 24,000 = 7200\)
Since the amount invested in Y can be different values, INSUFFICIENT.
Statement 2:Here, the amount invested in Y can be any monetary value between $0 and $24,000.
INSUFFICIENT.
Statements combined:Only Case 1 satisfies both statements.
In Case 1, the amount invested in Y = 10,000.
SUFFICIENT.