Grade 8 Ratio Quiz 1 draws its questions at random from 25 questions across these topics:
A few of the question types, with full solutions, so you know what to expect.
Simplifying Ratios. Simplify the ratio 15:20.
Answer: 3:4
The HCF of 15 and 20 is 5.
\( 15:20 = (15\div5):(20\div5) \)
Simplifying Ratios. Simplify the ratio 200:180.
Answer: 10:9
The HCF of 200 and 180 is 20.
\( 200:180 = (200\div20):(180\div20) \)
Simplifying Ratios. Simplify the three-part ratio 7:21:35.
Answer: 1:3:5
The HCF of 7, 21 and 35 is 7. Every part must be divided by the same number.
\( 7:21:35 = (7\div7):(21\div7):(35\div7) \)
Simplifying Ratios. Simplify the ratio 4 m : 250 cm.
Answer: 8:5
Convert to the same unit first: \( 4\text{ m} = 400\text{ cm} \).
\( 400:250 \). The HCF of 400 and 250 is 50.
\( 400:250 = (400\div50):(250\div50) \)
Simplifying Ratios. Simplify the ratio 12 min : 900 s.
Answer: 4:5
Convert to the same unit first: \( 12\text{ min} = 12\times60 = 720\text{ s} \).
\( 720:900 \). The HCF of 720 and 900 is 180.
\( 720:900 = (720\div180):(900\div180) \)