- Home
- NZ Year 8 Maths
- Ratios, Rates, and Proportions

# Ratios

- Intro Lesson: a4:23
- Intro Lesson: b6:37
- Intro Lesson: c2:53
- Lesson: 1a1:09
- Lesson: 1b0:53
- Lesson: 1c0:44
- Lesson: 1d0:47
- Lesson: 2a0:38
- Lesson: 2b1:08
- Lesson: 2c1:34
- Lesson: 2d0:57
- Lesson: 3a1:57
- Lesson: 3b1:11
- Lesson: 4a3:48
- Lesson: 4b2:34
- Lesson: 5a1:55
- Lesson: 5b4:07
- Lesson: 6a4:31
- Lesson: 6b6:57
- Lesson: 76:22
- Lesson: 85:23

### Ratios

#### Lessons

In this lesson, we will learn:

- Ratios With Decimals
- Ratios With Fractions
- Ratios in Different Units
- Application of Ratios

__Notes:__- A ratio should always be in its simplest/most reduced form (no common factors).
- The values in a ratio should always be integers if possible.
- A ratio can be scaled up/down by multiplying/dividing the ratio numbers by the same value. This process is called scaling, and the value used for scaling is called the scale factor.

- IntroductionIntroduction to Ratiosa)Introduction to Ratiosb)What are equivalent ratios?c)Ratios, Rates, and Proportions
- What are they?
- How are they different from each other?

- 1.Write the following ratios using ratio notation in lowest terms.a)5 km in 30 minutes.b)4 cases for $500.c)5 cupcakes need 325 g of flour.d)130 mm of precipitation in 2 days.
- 2.Write the following ratios in fraction form in lowest terms.a)3 hours in 1 week.b)35 g sugar in a 335 ml can of pop.c)4 servers to serve 6 tables with 4 guests each.d)22 sheep and 30 cows. What is the ratio of sheep to the total number of animals?
- 3.The following table shows the sugar and flour needed for different kinds of bakery.
Bakery

Sugar (g)

Flour (g)

Cake

40

120

Cookie

20

60

bread

30

450

a)Which 2 kinds of bakery have the same sugar-flour ratio? Show your work.b)What is the ratio of sugar needed for cookie to the total weight of sugar needed for all 3 kinds of bakery? - 4.
**Ratios With Decimals**Simplify the following ratios.

a)1.2 : 4b)1.4 : 1.6 - 5.
**Ratios With Fractions**Simplify the following ratios.

a)$\frac{2}{5} : 4$b)$\frac{2}{3} : \frac{7}{8}$ - 6.
**Ratios in Different Units**Simplify the following ratios.

a)$5 cm : 30 km$b)$4 hr 15 min : 3hr 30 min$ - 7.
**Application of Ratios**Jack and Jill are to share the candies in the ratio 3:4. If there are 21 candies in total, how many candies does each of them get?

- 8.Harry and Sally got some pocket money from their mother and they were to split it in the ratio 3:5. If Sally got $30, how much money in total did their mother give them?