# Simplify and compare rates

## Interactive practice questions

Which of the following is cheaper per item: $6$6 pencil cases for $\$24$$24 at Shop ZYX or 99 pencil cases for \54$$54 at Shop PWR?

a

What is the cost of a single pencil case at Shop ZYX?

b

What is the cost of a single pencil case at Shop PWR?

c

Hence which is the best place to buy pencil cases, if you want the best price per item?

Shop ZYX

A

Shop PWR

B

Shop ZYX

A

Shop PWR

B
Easy
Approx a minute

Which is cheaper: $148$148 mangos for $\$384.80$$384.80 at Shop ZYX or 252252 mangos for \453.60$$453.60 at Shop PWR?

An industrial detergent requires $19$19 mL of water to be added to every $1$1 mL of the detergent for safe usage.
How many litres of water must be added to $610$610 mL of detergent?

The admission for a concert starts at 6pm and closes at 7pm. If there are 900 people attending and they arrive at a constant rate, what is the flow of people per minute?

### Outcomes

#### 9P.NA1.05

Solve problems involving ratios, rates, and directly proportional relationships in various contexts (e.g., currency conversions, scale drawings, measurement), using a variety of methods (e.g., using algebraic 15 20 x 4 reasoning, equivalent ratios, a constant of proportionality; using dynamic geometry software to construct and measure scale drawings)