In 2000, the population at Arlington middle school was approximately 421 students. In 2010, the population was approximately 584 students. Find the percent of change in the population at Arlington middle school from 2000 to 2010 and identify it as an increase or decrease.

Question

In 2000, the population at Arlington middle school was approximately 421 students. In 2010, the population was approximately 584 students. Find the percent of change in the population at Arlington middle school from 2000 to 2010 and identify it as an increase or decrease.
A:27.9%; increase
B:27.9%; decrease
C:38.7%; increase
D:38.7%; decrease

2.The owner of an electronic store received a shipment of MP3 players at a cost of $64.25 each. If he sells the MP3 players for $99.99 each, what is the percent of the markup? Round to the nearest whole percent.
A:6%
B:36%
C:56%
D:62%

3.Find the final balance in an account with $730 invested at 3% annual simple interest for four years.
A:$735.48
B:$87.60
C:$817.60
D:$8,760.00

How do I solve these?

Ms. Sue · Answer

1. 584 - 421 = 163 100 * (163/421) = ________ 2. Try this one yourself. 3. Start with the formula: Interest = principle times rate times time I'll be glad to check your answers.