Q&A - PSLE Math

[NerdyMath]

An easier way solved by DS

6u + 60 =3p
5u-40=2p
4u+40 =2p

5u-40=4U+40
1U = 80

80X 6 = 480 [goose]
4x80+40 =360 [Duck ]

480-360 =120

[hoddle]

Hi

Need help on the below.

[NerdyMath]

Hi

Need help on the below.

28x18x15x4/5=6048

Find the base area.

Base area of A: base area of B
28x18 : 168
504 : 168

1.5 times x 168 = 252

6048/(252+504)= 8
8 x 252 = 2016 cm3
Solved by DS.

[NerdyMath]

Hi

Need help on the below.

24 x 6/10 = 14.4 papaya (sold)
24 x 4/10 = 9.6 papaya (left)

6/10 and 3/4 , the common denominator is 20

6/10= 12/20(papaya sold)
3/4= 15/20(apple sold)

Hence, 8/20 (papaya) and 5/20 (apple) will be left.

Also, don't forget about the 9.6 papaya earlier.

[][][][][][][][][9.6]
[][][][][]<---30-->

3u -> 30-9.6= 20.4
1u -> 20.4/3= 6.8

6.8 x 12 + 14.4 x $2.30 = $220.80
$0.40 x 15 x $6.80 = 40.80

$220.80+$40.80 = $261.60

(Sorry for the mistake! Was doing it late at night)

[NerdyMath]

Find that this is a great place for DS to help others, build a stronger foundations and be exposed to more questions. Hence, DS will be here to solve questions! Also, do pardon DS if his explanation/method is not clear.

[Ender]

-please help me with this question.

for the same duration,
Distance travelled by Eunike = 4/5 => 12/15
Distance traveled by Arthur = 2/3 => 10/15

Therefore ratio of distance traveled for the same duration E : A => 12:10=>6:5

Speed ratio is the same as above E : A = > 6u:5U
6u-5u = 12
u=12

Arther's speed is 5u = 5(12) =60km/h

[Ender]

-please help me with this question

this question was posted before,

Scenario 1 :
Flow rate into Tank A : B => 3:5 , Capacity of B = B- 5 litre

Scenario 2
Flow rate into Tank A:B =>4:3 , Capacity of B = 2XB

Common the A, as both scenario they filled completely, and hence both represent the capacity of A.

1) A:B=> 3:5 => 12u:20u , Capacity of B = 20u-5
2) A:B=> 4:3=> 12u:9u , Capacity of B = 2X9u= 18u

20u-5 = 18u
2u=5
u=2.5

Capacity of B = 18u=18(2.5) = 45 litre.

[alfretztay]

Hi Please advise on this question:

Machine A and Machine B working together take 7 days to finish producing 100 boxes of toys.
Mr Lee switched on Machine A and Machine B for 4 days, followed by Machine A alone for 7 days. Then he needed to switch on Machine B alone for 1 more day to complete producing the same 100 boxes of toys.
How long will Machine A alone take to produce the 100 boxes of toys?

Thanks in advance.

7A + 7B ——- (4A + 4B) + 7A + 1B
2B ——- 4A
1B ——- 2A
7A + 7B ——- 7A + 7 x 2A = 21A

Ans : 21 days.

[Ender]

In a factory , 585 of the workers are Chinese, 3/11 of the remainder are Malays and the rest are Indians. The Indians form 1/3 of the total number of workers. 1/2 of the Indians and 5/9 of the Malays are males.
(A) how many workers are there in the factory altogether?
(B) what is the ratio of the number of Indian male workers to the number of Malay male workers? Give your answer in its simplest form.


Please help. Thanks!!

Code: Select all

               Chinese(585) 
             /
Total Workers           Malay (3/11)
             \         /
              Others(?)
                       \
                        Indian (8/11)

8/11 X Others = 1/3
Others = 1/3 X 11/8 = 11/24

a) Therefore chinese make up of 24/24 -11/24 = 13/24

13/24 => 585
24/24 => 1080

b)Out of others,
Malays => 3/11 =>9/33
Males is 5/9 => 5/33

Indians=>8/11=>24/33
Males is 1/2=>12/33

Indian Male : Malay Male => 12:5

[Ender]

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Help Please.

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