Tag Archives: Maths

Primary 5 June Review 1

P5-June-Review 1

Ans:

1–  3

2–  3

3–  2

4–  3

5–  1

6–  2

7–  2

8–  4

40 : 45 = 8 : 9 = 16 : 18

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Primary 4 June Review 1

P4-June-Review 1

Ans:

1–  3

2–  3

3–  2

4–  4

5–  4

6–   4

7–  4

Lisa –> 4u

Michelle –> 5u

4u –>  60 marks

1u –>  15 marks

15 marks × 5 =  75 marks

 

8–  2

Joshua’s age –>  36 + 3  3/5 = 39  3/5 years old

39   3/5 — 5  3/10 = 34  3/10 years old×

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Primary 6 Prelims Revision 6

P6-Prelims-Ex 6

Ans:

1–  $1225

18% = 9/50

90% = 9/10

There­fore,

Bran­don   :   Charles
50        :     10
5          : 1

6u –> $1470

1u –> $245

$245 × 5u = $1225

 

2–  9/10 h

Time taken to fill 1/9 of the tank –>  2/5 ÷ 4 = 1/10 h

1/10 h × 9 = 9/10 h

 

3–  8 pen­tagons

3 × 5 = 15 match­sticks for the 3 extra pentagons

60 — 15 = 45 match­sticks (The num­ber of squares and pen­tagons are now the same)

Num­ber of match­sticks needed to make 1 square and 1 pen­ta­gon -> 4 + 5
= 9

45/9 = 5

5 + 3 = 8 pen­tagons

 

4–  10 hours

55 min = 11/12 h

11/12 h + 3/4 h = 1   2/3 h

5  1/2 h ÷ 11/12 h = 6 sets

6 × 1   2/3 h = 10 hours

 

5–  $40

85% — 55% = 30%

30% –> $12

100% –>  12/30 × 100 = $40

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Primary 3 Length, Mass and Volume Level 1 Ex 1

P3-Length, Mass and Volume-L1-Ex 1

Ans:

1–  1

2–  3

3–  3

4–  2

5–  2

6–  4

7–  2

8– 2

Mass of apple –>  640 g ÷ 4 = 160 g

160 g + 640 g = 800 g

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Primary 6 Prelims Revision 3

P6-Prelims-Ex 3

Ans:

1–  3 : 12 : 17

2–  4.95 cm

Length of the tank –>  180 cm³ ÷ 12 edges = 15 cm

33/100 × 15% = 4.95 cm

 

3–  100 balls

Total units of balls –>  5u + 4u = 9u

Units of balls in each bag in the end –>  9u/2 = 4.5u

5u — 4.5u = 0.5u —>  10 balls

1u –>  10 × 2 = 20 balls

20 × 5u = 100 balls

 

4–  540 km

5–  $24

1 blouse –> 1u

1 pair of jeans –>  1u + $12

3 pairs of jeans + 4 blouses –>  (1u + $12) × 3 + 4u = 7u + $36

7u + $36 -> $204

7u –>  $204 — $36 = $168

1u –>  $24

 

6–  891 beads

Red : Blue + Green
4   : 5

Blue : Green
3    :    8     –> 11u

Adjust the units for the blue and green beads such that they are the same in both cases.

Com­mon mul­ti­ple of 5 and 11 is 55u

There­fore,

Red  :  Blue + Green
44   : 55

Blue  :  Green
15   : 40

Red  :  Blue  :  Green
44 :    15   : 40

44u — 40u = 4u –>  36 beads

1u –>  9 beads

44u + 55u = 99u —->  9 beads × 99 = 891 beads

Con­tinue read­ing

  

Primary 2 Whole Numbers Level 3 Ex 2

P2-Whole Numbers-L3-Ex 2

Ans:

1–  8 mark­ers

 

2–  8 stamps

3–  569 stick­ers

4–  776 stamps

5–  40 pupils

Qn 5

Num­ber of girls –> 30 ÷ 3 = 10

30 + 10 = 40 pupils

 

6–  9 beads

Total num­ber of beads they had –>  76 + 45 = 121

130 — 121 = 9 beads

 

7–  720 stick­ers

Num­ber of stick­ers Tanya has –>  341 + 38 = 379

379 + 341 = 720 stick­ers

 

8–  537 stamps

  

Primary 6 SA1 Revision 12

P6-SA1-Ex 12

Ans:

1–  175

2–  $43.50

70% of the price –>  $101.50

30% –>  $101.50/70 × 30 = $43.50

 

3–  (3+ 6) kg

Alan’s mass ->  (+ 3) kg

Nicholas’ mass ->  (m + 3) — 2 = (+ 1) kg

Brett’s mass ->  (+ 1) + 1 = (+ 2) kg

(m + 3) + (+ 1) + (+ 2) = (3+ 6) kg

 

4–  195 km

1  1/2 h× 80 km/h = 120 km

45/60 h × 100 km/h = 75 kg

120 km + 75 km = 195 km

 

5–  $6441.60

Earn­ings in Jan­u­ary –>  122/100 × $6000 = $7320

Earn­ings in Feb­ru­ary –>  88/100 × $7320 = $6441.60

 

6–  30 peo­ple

Frac­tion of men  –>  30/100 = 3/10 = 9/30

Frac­tion of men if 10 women alighted –>  45/100 = 9/20

Women –>  30u — 9u = 21u

20u — 9u = 11u

10u –>  10 women

30 u –>  30 people

Con­tinue read­ing

  

Primary 6 SA1 Revision 11

P6-SA1-Ex 11

Ans:

1–  22

2– $100.00

3–  15 000.02 m

4–  7/8 ,  5/6 ,   1/2 , 1/4

5–  5 p.m.

2 h 15 min before 11.45 a.m. –>  9.30 a.m.

7 h 30 min after 9.30 a.m. –>  5 p.m.

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Primary 5 SA1 Revision 5

P5-SA1-Ex 5

Ans:

1–  200 0002 hun­dred thousands

2–  15 600

3–  298

4–  9

5–  9 : 7

$81 — $18 = $63 (Marianne’s)

Ali­son   :   Mar­i­anne
81       :      63
–>    9     : 7

 

6–  3

15 × 3/10 = 4 1/2

4   1/2 ÷  3/2 = 3

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Primary 4 SA1 Revision 5

P4-SA1-Ex 5

Ans:

1–  Twelve thou­sand, seven hun­dred and ninety-eight

2–  2568

3–  1885 / 1886 /1887 /1888/1889/1891/1892/1893/1894

4–  5/9

5–  875

6–  761

        761          ,        12 870     ,     24 969      ,     37 058    ,    49 137
( +12 109)     (+ 12 099)      (+ 12 089 )     (+ 12 079)

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