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P5 MATHS

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Taken from Learning Maths Book 5A

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Do these sums with the use of a calculator.

1. Add107.83land64.18l=

2. Subtract$937.95from$3549.20=

3. Multiply2.864gby47=

4. Divide736.4kgby35=

5. Subtract20.346lfrom548.6l=

1. Press C 1 0 7 . 8 3 + 6 4 . 1 8 = 172.01 l2. Press C 3 5 4 9 . 2 0 – 9 3 7 . 9 5 = $2611.253. Press C 2 . 8 6 4 × 4 7 = 134.608 g

4. Press C 7 3 6 . 4 ÷ 3 5 = 21.04 kg5. Press C 5 4 8 . 6 – 2 0 . 3 4 6 = 528.254 l

Solutions:

P5 MATHS


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Do these word problems. Show your working clearly in the space provided.

1. AdozensimilarT-shirtscost$162.60.HowmuchdoeseachT-shirtcost?

2. MrsMatthewbought12.45kgofprawnsand 3__ 4 kgofsquids.Iftheprawnscost$30perkg

andthesquidscost$18perkg,howmuchdidMrsMatthewspendaltogether?

1. $162.60 ÷ 12 = $13.55EachT-shirtcosts$13.55.

2. 3 _ 4 × 1000 = 750 g = 0.75 kg

(12.45 × $30) + (0.75 × $18) = $387 Mrs Matthew spent $387 altogether.

Solutions:

P5 MATHS


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Do these word problems. Show your working clearly in the space provided.

1. The mass of a metal container, together with 10 identical metal balls, is 79.15 kg.Ifthemassofthemetalcontaineris16.75kg,whatisthemassofeachmetalball?

2. Joeybought17.3mofcloth. 1__ 5 oftheclothwasdamagedandsheusedtheresttomake4

similarcurtains.

(a) HowmuchclothdidJoeyusetomakeonesuchcurtain? (b) IfJoeysoldeachcurtainfor$19.90,howmuchmoneywouldshereceiveinall?

1. 79.15 – 16.75 = 62.4 kg 62.4 ÷ 10 = 6.24 kg The mass of each metal ball is 6.24 kg.

2. (a) 1 – 1 _ 5 = 4 _ 5 4 _ 5 × 17.3 = 13.84 m

13.84 ÷ 4 = 3.46 m Joey used 3.46 m of cloth to

make one such curtain.

(b) 4 × $19.90 = $79.60 She would receive $79.60 in all.

Solutions:

P5 MATHS


SAPMATP5_W24/4

Taken from Mental Mathematics Book 5

Solutions: 1. 1 ___ 12 2. 3 ___

50 3. 4 ___ 15 4. 1 ___

12 5. 3 ___ 25 6. 3 ___

20 7. 1 __ 5 8. 3 ___

50 9. 5 ___ 12 10. 5 ___

22

Mental Maths: Dividing Fractions by Whole Numbers

STRATEGY

Do these sums mentally.

1. 16___ 24 ÷8= 6. 18___ 20 ÷6=

2. 27___ 50 ÷9= 7. 32___ 40 ÷4=

3. 12___ 15 ÷3= 8. 42____ 100 ÷7=

4. 39___ 36 ÷13= 9. 10____ 12 ÷2=

5. 15___ 25 ÷5= 10. 55___ 22 ÷11=

Findthevalueof 25___ 60 ÷5.

Step1: Tofindthenumeratoroftheanswer,

25÷5=5 [dividethenumeratorofthefractionbythedivisor]

Step2: Reducethefractiontoitslowestterm,

5___ 60 ÷5÷5 = 1 ___ 12

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