5.1 Ratio notation, simplifying and sharing — Practise with help
Try each question first. Open a hint if you are stuck, the next step for one concrete move, and the full working only to check.
Warm-up: remember
Answer these from memory. Do not look back at the section.
- Simplify .
- Work out .
Check the warm-up
- .
- .
If an answer differs, revisit Section 4.1 for simplifying fractions and Section 1.3 for working with negative numbers.
Practise with help
1. Simplify the ratio .
Hint
Find a number that divides both parts exactly.
Next step
Both parts divide by 6.
Full working
divides by 6 to give . Check that .
2. Share £84 in the ratio .
Hint
Add the ratio parts to find the number of equal parts.
Next step
parts, so one part is .
Full working
The shares are and . Check: .
3. A recipe mixes flour and sugar in the ratio . A baker uses 250 g of sugar. How much flour is needed?
Hint
The 2 parts stand for 250 g. Find the value of one part first.
Next step
One part is g. Flour is 5 parts.
Full working
Flour is g. Check: .
4. Earlier learning. In a class of 30 pupils, 12 walk and the rest take the bus. What fraction of the class take the bus?
Hint
The fraction is the bus pupils over the total. Find the bus number first.
Next step
pupils take the bus.
Full working
of the class take the bus.