Arithmetic Word Problems Flashcards

An employee earns $18/hour for regular time and 1.5× for overtime. She works 45 hours in one week. What are her total weekly earnings?

Answer: $855

40 regular hours × $18 = $720; 5 overtime hours × $27 = $135; total = $855.

A train 300 meters long passes a stationary pole in 15 seconds. What is the train's speed in km/h?

Answer: 72

Speed = 300 ÷ 15 = 20 m/s; 20 × 3.6 = 72 km/h.

A $200 item is discounted 15%, then 8% sales tax is applied. What is the final price?

Answer: $183.60

$200 × 0.85 = $170; $170 × 1.08 = $183.60.

If 8 pipes fill a tank in 6 hours, how long will 12 pipes take to fill the same tank?

Answer: 4 hours

Total pipe-hours needed = 8 × 6 = 48; time with 12 pipes = 48 ÷ 12 = 4 hours.

A person invests $5,000 at 4% simple interest per year. How much total interest is earned in 3 years and 6 months?

Answer: $700

I = $5,000 × 0.04 × 3.5 = $700.

A box contains red and blue marbles in a ratio of 3:5. If there are 24 red marbles, how many marbles are in the box in total?

Answer: 64

3 parts = 24, so 1 part = 8; total 8 parts × 8 = 64 marbles.

Maria drives to work at 60 mph and returns home along the same route at 40 mph. What is her average speed for the entire round trip?

Answer: 48 mph

Average speed = 2 × 60 × 40 ÷ (60 + 40) = 4,800 ÷ 100 = 48 mph.