Q&A - P5 Math

[guchengyouzi]

Kindly help with this too

Volume of 48 big books is 48b
Volume of 60 small books is 60s
48b = 60s
Volume of 10 small and 12 big is 10s + 12b
Volume left in Box A is 48b - (10s + 12b)

since 60s = 48b, therefore 10s = (48/6)b
Volume left in Box A
= 48b - (10s + 12b)
= 48b - ((48/6)b + 12b)
= 48b - (8b + 12b)
= 48b - 20b
= 28b
28 big books

[numeric]

. Please help with this one too . Thanks for all the help on advance

[Whitearies]

[quote="speedmaths.com"][quote="Whitearies"][quote="speedmaths.com"][quote="Whitearies"]There were 3/5 as many children as audlts in the bus. At the next bus stop, 3 children boarded and 2 adults alighted from the bus. Then, there were 5/6 as many children as adults on the bus. How many children were there on the bus at first?

Anyone can help to solve this question without using algebar mathod
Hi,




Algebar Method (Advanced Model Method) : (Had confirm with two diff sch teacher, both said its actually algebar method)

Before : 3 : 5 (Lets it call units)
+ 3 children board
- 2 adults alight (Lets it call parts)
After : 5 : 6

Children :
3u + 3 = 5p (Total must be the same as adults therefore x6 here)
x6
18u + 18 = 30p

Adults :
5u - 2 = 6p (Total must be the same as children therefore x5)
x5
25u - 10 = 30p

Therefore :
18u + 18 = 25u - 10
18 + 10 = 25u - 18u
28 = 7u
4 = u

4 x 3 = 12 children

But the school teacher said P5 have not learn algebar :
Therefore this is the method from school teacher:

+3 children board
-2 adults alight
Before : After :
3 : 5 5 : 6
6 : 10 10 : 12
9 : 15 15 : 18
12 : 20

12 + 3 = 15
20 - 2 = 18
15 : 18
5 : 6

Therefore there are 12 children at first

[Whitearies]

One more problem too ,

Hi,

You can try using
the "Advanced Model Method" or the "Bags and Boxes" method,
(or try the more algebraic version: "u" and "p".)

Please see the example on Page 1104 below.

http://www.kiasuparents.com/kiasu/forum ... tart=11030


Please let us know if you still need help.

Cheers



speedmaths
.

This method is really good and fast. Thanks speedmaths ^-^
Before 1 : 1 (units)
+4 50 cents coins
-20 10 cents coins
After 17 : 5 (parts)

50 cents coins :
1u + 4 = 17p
x5
5u + 20 = 85p

10 cents coins :
1u - 20 = 5p
x17
17u - 340 = 85p

17u - 340 = 5u + 20
17u - 5u = 20 + 340
12u = 360
u = 30

50cents = 30 x 0.5 = $15
10cents = 30 X 0.1 = $3
Total : $15 + $3 = $18

or (not sure is this method correct?) anyone know?
+ 4 50cents coins
-20 10cents coins

50cents : 10cents
After 17 : 5
Before 13 : 25

After :
17 x 0.5 = $8.50
5 x 0.1 = $0.50
Total $ 9.00

Before :
13 x 0.5 = $6.50
25 X 0.1 = $2.50
Total $ 9

$9 + $9 = $18

Thanks

[guchengyouzi]

There were 3/5 as many children as audlts in the bus. At the next bus stop, 3 children boarded and 2 adults alighted from the bus. Then, there were 5/6 as many children as adults on the bus. How many children were there on the bus at first?

Initially adults to children 3:5
``````````adults`````````children
Initially`````3u``````````````5u

Then 3 adults boarded and 2 children alighted
``````````adults`````````children
Initially`````3u``````````````5u
Then``````3u + 3``````````5u - 2
Therefore````5p`````````````6p

3u + 3 = 5p
5u - 2 = 6p
solve for u

[Sruthi]

There were 3/5 as many children as adults in the bus. At the next bus stop, 3 children boarded and 2 adults alighted from the bus. Then, there were 5/6 as many children as adults on the bus. How many children were there on the bus at first?


The method from the teacher not able to understand .
How did we get 12:20 .
Can anyone explain please ?

[guchengyouzi]

There were 3/5 as many children as adults in the bus. At the next bus stop, 3 children boarded and 2 adults alighted from the bus. Then, there were 5/6 as many children as adults on the bus. How many children were there on the bus at first?


The method from the teacher not able to understand .
How did we get 12:20 .
Can anyone explain please ?

May be the question is mixed up.
3 adults boarded
2 children alighted

[guchengyouzi]

Please help with this

Spending ratio Noel to Kim 1:3
```````````Noel`````````Kim
Spending````1u```````````3u

Money remaining
``````````````Noel`````````Kim
Remaining````360 -1u```````240 - 3u

Remaining money ratio Noel to Kim 3:1
``````````````Noel`````````Kim
Remaining````360 -1u```````240 - 3u
`````````````3p```````````1p

360 - u = 3p
240 - 3u = p

[Whitearies]

There were 3/5 as many children as adults in the bus. At the next bus stop, 3 children boarded and 2 adults alighted from the bus. Then, there were 5/6 as many children as adults on the bus. How many children were there on the bus at first?


The method from the teacher not able to understand .
How did we get 12:20 .
Can anyone explain please ?

How to post pic here? ^-^

[Whitearies]

There were 3/5 as many children as adults in the bus. At the next bus stop, 3 children boarded and 2 adults alighted from the bus. Then, there were 5/6 as many children as adults on the bus. How many children were there on the bus at first?


The method from the teacher not able to understand .
How did we get 12:20 .
Can anyone explain please ?

How to post pic here? ^-^