Q&A - P3 Math

[SAHM Chew]

tianzhu:

SAHM Chew:

Please help


A square carpet covers 7/8 of the floor. What is the area of the uncovered floor if the carpet has a side of 7m?

Thanks

Hi

Area of square carpet ------ 7*7 ------- 49

7 units ------- 49

1 unit -------- 7

Area of uncovered floor ------- 1/8 ------ 1 unit ------- 7

Best wishes

Thanks Tianzhu

[Cher2101]

Hi parents how do you teach kid on this sum?


Mrs lim bought 5 chickens and 1 duck for $83.
Mrs Chen bought 2 chickens and 2 ducks for $62.
How much does each chicken cost?
How much does each duck cost?

Thank you

[tianzhu]

Cher2101:

Hi parents how do you teach kid on this sum?


Mrs lim bought 5 chickens and 1 duck for $83.
Mrs Chen bought 2 chickens and 2 ducks for $62.
How much does each chicken cost?
How much does each duck cost?

Thank you

Hi

Good Morning.

You may solve it pictorially or use letters of the alphabet.

2C + 2D -------- 62

This means 1C + 1D -------- 31

5C + 1D -------- 83

4C + (1C + 1D) ------- 83

4C + 31 -------- 83

4C ------- 52

C -------- 13

D -------- 31 -13 ------- 18.

If you prefer the pictorial way, substitute the C and D with boxes and circles or other shapes.

Best wishes

[kwcllf]

5C + 1D = 83


Double it up (x2), you get:
10C + 2D = 166
2C + 2D = 62 (from the other equation)

When you minus out the two equations, you will be left with:
8C = 104 (the 2D cancels out each other)
1C = 104/8 = 13

To find out D,

5C + 1D = 83
5 (13) + 1D = 83
1D = 83 - 65 = 18

I have taught my P3 kid substitution, like in the other method.But, she seems to have problem grasping and mastering it.

But if I show her this method here, she seems to understand much easier.

[peapot]

hi, pls help me on this


The total mass of Shirley and Johnis 111kg. The total mass of Shirley and Kee Boon is 115kg. Shirley is 2 times as heavy as John. What is Kee Boon’s mass?

[SAHM Chew]

peapot:

hi, pls help me on this


The total mass of Shirley and Johnis 111kg. The total mass of Shirley and Kee Boon is 115kg. Shirley is 2 times as heavy as John. What is Kee Boon's mass?

Kee Boon is 41kg?

Shirley x x
John x

Total is 111kg so x = 111kg / 3 = 37kg
John is 37kg
Shirley is 2 times = 37kg x 2 = 74kg
Shirley and Kee Boon is 115kg.
Kee Boon = 115kg - 74kg = 41kg

[peapot]

Oh! Ya hoh! I didn’t notice that Shirley and John same size unit. Thanks SAHM Chew!! You still not sleeping?

[SAHM Chew]

peapot:

Oh! Ya hoh! I didn't notice that Shirley and John same size unit. Thanks SAHM Chew!! You still not sleeping?

Not yet.. haha... you wanna drink coffee???

[kiasustar]

Cindy had twice as much as Ivy. After Cindy spent $36 & Ivy spent $12, Ivy had twice as much as much the money as Cindy. How much had Cindy left ?


Anyone can help? Thank u v much

[kiasustar]

Ms Wang had $400 more than Mr Sim.at first. After Mr Sim had spent $340, Ms Wang had 5 times as much as Mr Sim. How much did Ms Wang have at first?


Anyone? Tq