Q&A - P4 Math

[jwxh]

the answer given may be wrong. i have checked the question and the figures are right. do u have the workings for the question?

[tianzhu]

jwxh:

the answer given may be wrong. i have checked the question and the figures are right. do u have the workings for the question?

Hi

Siti, Rahmesh and Peter had 528 stickers at first. Siti bought another 32 stickers, Ramesh gave 1/5 of his stickers away and Peter was given as many stickers as he had at first by his father. In the end, all three of them had equal number of stickers. Find the number of stickers Siti had at first.

Change 32 to 33, and you’ll get Siti ----- 171 stickers@first.

Due to time constraints, I’ll not draw the MD, just some pointers

In the end

Siti ------- 4u

Ramesh ------ 4u

Peter ------ 4u

At first

Siti ------- 4u – 33

Ramesh ------ 5u

Peter ------ 2u

11u ------ 561

1u ------ 51

You may continue from here.

Best wishes

[jwxh]

tks all of u.

[cathycho]

Can someone help me on these?


1. 50 is the estimated quotient when a 3 digit number is divided by a 1 digit number. Think of two possible numbers that can give this quotient. The. Check if your answer is correct.

2. A 3 digit number when rounded off to the nearest ten and the nearest hundred will produc the same answer. What is the number?

[meatloaf]

Hi


Can someone help me?

Rashid made 120 more buns than Sam. After Rashid sold 57 buns and Sam sold 105 buns, Rashid had 4 times as many buns as Sam. How many buns did Sam have at first?

Many THanks!

[tianzhu]

meatloaf:

Hi


Can someone help me?

Rashid made 120 more buns than Sam. After Rashid sold 57 buns and Sam sold 105 buns, Rashid had 4 times as many buns as Sam. How many buns did Sam have at first?

Many THanks!

Hi

Hope this helps.

Best wishes

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[cftan]

Hi,


Pls help to advice.

Which of the following is the best estimate for 384 x 23?
(1) 380 x 20
(2) 400 x 20

Ans is (2). Isn’t (1) a closer estimate?

Thanks.

[BigDevil]

With DD in P4, I’m also interested to find out how to do this "estimation".

Just by visually, or have to work out the problem?

In the question posted by cftan,
384 x 23 = 8832
380 x 20 = 7600
400 x 20 = 8000

So the better estimate is 400 x 20 (difference of 832 from actual answer,
as compared to difference of 1232 for 380 x 20).

[cftan]

The topic on "estimation" is a bit tricky for me.


Estimate 1894 / 5

I thought the nearest would be 1890 / 5 but the answer is 2000 / 5.

Can someone advise. Many thanks.

[HAPPYH]

BigDevil:

With DD in P4, I'm also interested to find out how to do this \"estimation\".

Just by visually, or have to work out the problem?

In the question posted by cftan,
384 x 23 = 8832
380 x 20 = 7600
400 x 20 = 8000

So the better estimate is 400 x 20 (difference of 832 from actual answer,
as compared to difference of 1232 for 380 x 20).

My goodness. I always tell my DD rounding of to the nearest 10 will be the better estimate. Unless they do proper multiplication, they will not know the correct answer. Really this estimation confusing.