20/5 Concept Check

Mark can type 44 words in 2 minutes. Which of the following is equivalent to that rate?

• 62 words in 3 minutes

• 84 words in 4 minutes

• 100 words in 5 minutes

• 132 words in 6 minutes

Hasan buys 2.4 kg of mangoes, which costs him 360 Tk. What is the price (in Tk) for 1 kg of mangoes?

Do not include units with your answer.

Saima read 50 pages of her book in 40 minutes. How many pages did Saima read per minute?

Give your answer as a decimal. Do not include units with your answer.

A store sells oranges for 55 Tk each. The store also sells bags of 7 oranges for 377 Tk. Is it more cost-effective to buy individual oranges or bags of oranges? (In other words, which one offers a better price per orange?)

• Individual oranges

• Bag of oranges

Answer explanation

We calculate the unit price for the bag of oranges to compare it to the price of an individual orange. Each orange in a bag of oranges costs 377 ÷ 7 = 53.86 Tk. This is less than the 55 Tk that an individual orange costs, so buying the bag of oranges is more cost-effective.

A 250 mL refill of dishwashing liquid costs 70 Tk.

A 500 mL bottle of dishwashing liquid costs 150 Tk.

A 1 L bottle of dishwashing liquid costs 270 Tk.

Which size of dishwashing liquid is the most cost-effective?

• 250 mL

• 500 mL

• 1 L

Lana can run 200 m in 40 seconds. What is her speed in m/s?

Do not include units in your answer.

It took Robert 3 hours to drive to his parents' house. If he drove at an average speed of 45 miles per hour, how many miles did he drive?

Do not include units in your answer.

Eunice's office is 30 miles away from her house. If she drives at a speed of 60 miles per hour, how long does it take her to get to the office?

Give your answer in minutes. Do not include units in your answer.

Beena cycled for 45 minutes this morning. If she cycled at an average speed of 20 km per hour, how many kilometers did she go?

Do not include units in your answer.