Lemmara logoLemmaraWorked solution

0580/31 May/Jun 2021, Question 1: Number Review: Mixed Practice

Cambridge IGCSE Mathematics 0580 · Paper 31 (Core) · Calculator · 16 marks

اقرأ هذا الحل مشروحاً بالعربي ←

The question, in short

Work through money, fraction, percentage, ratio and profit problems: costs of strawberries and cream, buying pineapples, sharing biscuits, cake sales, splitting sweets, and dessert pricing.

Summarised in our own words. Use the official paper for the exact wording and any diagrams.

Part (a) · 3 marks

Find the total cost of 1.2 kg of strawberries at $4.20 per kg plus 125 ml of cream at $8.56 per litre.

  1. 1Strawberries: 1.2 × 4.20 = $5.04
  2. 2Cream: 125 ml = 0.125 litres, 0.125 × 8.56 = $1.07
  3. 3Total = 5.04 + 1.07 = $6.11

Answer6.11

Part (b) · 3 marks

With $20 and pineapples at $1.45 each, find the largest number Ravi can buy and his change.

  1. 120 ÷ 1.45 = 13.79…, so he can buy 13 pineapples
  2. 213 × 1.45 = $18.85
  3. 3Change = 20 − 18.85 = $1.15
  4. 4Number of pineapples 13, change $1.15

AnswerNumber of pineapples 13, Change $1.15

Part (c) · 3 marks

From 72 biscuits, give 2/9 away, then 3/7 of the remainder; find how many Abraham has left.

  1. 1To grandmother: 2/9 × 72 = 16, leaving 72 − 16 = 56
  2. 2To cousin: 3/7 × 56 = 24
  3. 3Biscuits left = 56 − 24 = 32

Answer32

Part (d) · 1 mark

Flo makes 84 cakes and sells 35; calculate the percentage of cakes sold.

  1. 135/84 × 100 = 41.66… ≈ 41.7%

Answer41.7 or 41.66 to 41.67

Part (e) · 2 marks

Share 132 sweets between Beatrix and Volker in the ratio 5 : 7; find each amount.

  1. 15 + 7 = 12 parts, 132 ÷ 12 = 11
  2. 2Beatrix = 5 × 11 = 55
  3. 3Volker = 7 × 11 = 77

AnswerBeatrix 55, Volker 77

Part (fi) · 2 marks

Desserts sell for $24 and cost $12.80 to make; work out the percentage profit.

  1. 1Profit = 24 − 12.80 = $11.20
  2. 2Percentage profit = 11.20/12.80 × 100
  3. 3= 87.5%

Answer87.5

Part (fii) · 2 marks

Cost rises to $13.60; find the new selling price that keeps the same percentage profit.

  1. 1New price = 13.60 × (1 + 87.5/100)
  2. 2= 13.60 × 1.875
  3. 3= $25.50

Answer25.50

Stuck on a step? Read the free lesson: Number Review: Mixed Practice

Practise more number review: mixed practice questions

Real 0580 past-paper questions, marked on your working like the exam, with a worked solution for every part.

Practise free on Lemmara

More past-paper questions on number review: mixed practice

Also searched as: 0580/31/M/J/21 · 0580_s21_qp_31 · 0580 s21 31 · question 1.
Lemmara is an independent study tool, not affiliated with or endorsed by Cambridge International Education. The worked solutions are Lemmara’s own.