Choose the one alternative that best completes the statement or answers the question.
-For a fixed amount of principal, the simple interest varies jointly with the rate and the time. If the simple interest is $\$ 1200$ when the rate is $4 \%$ and the time is 6 years, find the simple interest when the rate is $5 \%$ and the time is 10 years.
A) $\$ 5000$
B) $\$ 2750$
C) $\$ 250$
D) $\$ 2500$

Question

Quizplus · Accepted Answer

Simple interest is calculated as $I = P \times r \times t$, where $I$ is the interest, $P$ is the principal, $r$ is the rate, and $t$ is the time. Given $I = \$1200$, $r = 4\%$, and $t = 6$ years, we can find the principal using the formula. Then, using the same principal, we calculate the interest for $r = 5\%$ and $t = 10$ years. The correct answer is $\$2500$, indicating that the interest increases with both the rate and the time.

Choose the One Alternative That Best Completes the Statement or Answers