Q&A - P4 Math

[Always21]

quekcc:

Always21:

Pls help with this


There are three bottles of beads. The second bottle contains 5/7 of the number of beads in the first bottle. The third bottle contains 1/2 of the number of beads in the second bottle. The difference between the number of beads in the first and third bottle is 27. What is the sum of the beads in the three bottles?

Really need help

Thanks in advance.

One way is

the lcm of 2 and 7 is 14.

So you can let the number of beads in 2nd bottle be 10 units, then 3rd bottle will be 5 units and 1st bottle will be 14 units.

14 - 5 = 9 units = 27 beads, so 1 unit = 3 beads.

Sum = 3 x (14 + 10 + 5) = 3 x 29 = 3 x (30 - 1) = 90 -3 = 87.

Sorry,
My son was asking if there is a way to use model drawing as the one you have are using algebra which they are not taught yet

Sorry for the trouble.

[Oldschool]

Always21:

Sorry,
My son was asking if there is a way to use model drawing as the one you have are using algebra which they are not taught yet

Sorry for the trouble.

Hi,

http://i40.tinypic.com/335d2ya.jpg\">

Regards

[Always21]

Oldschool:

Always21:

Sorry,
My son was asking if there is a way to use model drawing as the one you have are using algebra which they are not taught yet

Sorry for the trouble.

Hi,

http://i40.tinypic.com/335d2ya.jpg\">

Regards

Thank you very much. He got it!! Thanks

[Always21]

Oldschool:

Always21:

Sorry,
My son was asking if there is a way to use model drawing as the one you have are using algebra which they are not taught yet

Sorry for the trouble.

Hi,

http://i40.tinypic.com/335d2ya.jpg\">

Regards

Thank you very much. He got it!! Thanks

[shurley197323]

tianzhu:

shurley197323:

[Thank you & Sorry, Tianzhu,

I still can't get ( 1600 ) & (36) ?

Can help to show me step by step ?

Thks in advance.

Hi

From 1 to 79, there are 40 number of odd numbers.

sum of odd numbers from 1 to nth term ------ n*n (n square)

40*40 ----- 1600

36 is the sum of odd numbers from 1 to 11 (1+3+5+7+9+11)

Best wishes

OK. Thanks Tianzhu

[peapot]

Hi everyone! Pls help me with following q.


Mr Lee arranged some chairs in 15rows, such that there were equal number of chairs in each row. When he removed 5 rows of chairs and placed them on the remaining 10rows, the number of chairs in each row increased by 6. What was the number of chairs in each row at first?

[tianzhu]

peapot:

Hi everyone! Pls help me with following q.


Mr Lee arranged some chairs in 15rows, such that there were equal number of chairs in each row. When he removed 5 rows of chairs and placed them on the remaining 10rows, the number of chairs in each row increased by 6. What was the number of chairs in each row at first?

Hi

10*6 ----- 60

These 60 chairs were from the original 5 rows.

Number of chairs in each row at first ------ 60/ 5 ------ 12

Best wishes

[peapot]

Oh! Tianzhu Thks!! You make it looks so easy!!


I have one more q on perimeter, no dimensions given. Need to post pic.

[milo-cupcake]

Can anyone help with the following question?


http://i40.tinypic.com/333z4v4.jpg\">

Thanks in advance.

[The Right Equation]

milo-cupcake:

Can anyone help with the following question?


http://i40.tinypic.com/333z4v4.jpg\">

Thanks in advance.

concepts involved:
1) total quantity remains unchanged
2) work backwards

method 1:
http://i44.tinypic.com/35koqi8.jpg\">

method 2:
http://i39.tinypic.com/fn45q8.jpg\">

method 2 is for explanation purposes (since if it is a p4 qn, not allowed to use ratio)