☰ خطة العام · الرياضيات (بالإنجليزية)

Term 1 review

الأسبوع 15 · مراجعة الفصل الأول · 3 دروس
3

Review: expressions, patterns and mixed problems

Discover Mathematics P5: Term 1, Units 1–6, Review
GoalReview the order of operations, grouping symbols, number patterns and multistep stories.
New words
order of operations · grouping symbols first, then × and ÷, then + and −rule · what you do to a term to get the next onemultistep problem · a problem needing more than one calculation
Explanation

Order of operations: work inside parentheses and brackets first (from the inside out), then multiply and divide from left to right, then add and subtract from left to right. A number pattern follows a rule such as add 5 or multiply by 2; find the rule by checking every pair of neighbours. For a story with many steps, write each step as a short number sentence, keep the units, estimate, and check that the answer makes sense.

StepDo first
1( ) and [ ], inside out
2× ÷
3+ −
Worked examples
StepWorkResult
112 − 48
23 × 824
324 ÷ 212
45 + 1217
Work out 5 + 3 × (12 − 4) ÷ 2. Parentheses: 12 − 4 = 8. Then 3 × 8 = 24 and 24 ÷ 2 = 12. Finally 5 + 12 = 17.
Find the rule and the 10th term of 7, 12, 17, 22. The rule is add 5. The 10th term is 7 + 9 × 5 = 52.
147125?300
A school buys 6 boxes of markers at 24.5 LE each and 4 packs of paper at 31.25 LE each. It pays 300 LE. 6 × 24.5 = 147 and 4 × 31.25 = 125. Total 272 LE. Change: 300 − 272 = 28 LE.
Class activity

Mixed problem mat. Make three cards: one with an expression, one with a pattern and one with a shop story. The grown-up chooses the numbers. The child solves each card, explains the first step out loud, and checks it by estimating.

Practice
1
Work out 48 − 6 × 4 + 12 ÷ 3.
2
Work out (9 + 3) × (10 − 4) ÷ 2.
3
Find the rule of 3, 6, 12, 24 and the 7th term.
4
Start at 2.5 and add 1.25. Write five terms.
5
Marwan buys 3 kg of rice at 12.5 LE per kg and 2 kg of lentils at 8.25 LE per kg. He pays 100 LE. Write one expression for his change and find it.