Q&A - PSLE Math

[MathIzzzFun]

peggy:

Please help with this.


Denise had 288 beads more that Annie. After Denise lost 1/6 of her beads and Annie lost 75% of her beads, Denise had 303 more beads that Annie. How many beads did Denise have at first ?

thanks.

Hi

Annie --> 12 units (** 1/6 & 3/4 --> lowest common denominator = 12)
Denise --> 12 units + 288

After Denise lost 1/6 beads and Annie lost 3/4 of her beads:
1/6 of Denise --> 2 units + 48
Denise, left --> 10 units + 240
Annie, left --> 1/4 x 12 units = 3 units

10 units + 240 = 3 units + 303
1 unit --> 9

Denise, at first --> 12 x 9 + 288 = 396
Denise had 396 beads at first.

cheers.

[peggy]

MathIzzFun,


Thanks so much for your prompt reply.

Have a nice day !

[Dreamerz]

tianzhu:

Dreamerz:

Hi tianzhu,

Q1 the total of the two baskets is given as 960.
Basket A has 600 while B has 360.

dont know y they test understanding of our language rather than being straight forward ... sigh

Hi

First thing first, did you make any changes to the original question?

Do take note that 600 and 360 were not given in your original question.Please post the original question as it is shown in your source.

1) mr tan had a total of 960 fruits. 30% of the 600[/u] fruits in basket A were oranges and the rest were pears. 40% of the fruits in basket B were pears and the rest were oranges. after some fruits were transferred from A to B and B to A, 25% of the fruits in basket A and 75% of the fruits in basket B were oranges. how many fruits are there in basket A in the end?

Best wishes[/quote]

sorry just realised that the 600 was missing

[tianzhu]

Dreamerz:

sorry just realised that the 600 was missing

Hi

With the inclusion of 600 in the original question, then it becomes a regular question seen in past years papers.

This question touches on simultaneous concept.

Students who are familiar with SE may use them. Otherwise, they may solve the two equations pictorially or use Units and Parts or letters of alphabet to represent the two variables.

Due to time constraints, I’ll not be doing the slide, but will be using Units and Parts as an illustration. To convert to MD way, just substitute the Units with boxes or other shapes and the Parts with circles or other shapes

Basket A
Oranges ------ 180
Pears ------ 420

Basket B
Oranges ------ 216
Pears ------ 144

After the transfer

Basket A
Oranges ------ U
Pears ------ UUU

Basket B
Oranges ------ PPP
Pears ------ p

U + PPP ------- 396
UUU + P -------564

UUUU + PPPP ------- 960
U + P ------ 240

UU + (U + P) ------564
UU + 240 ------ 564
U ------ 162

Number of fruits in Basket A in the end ------ UUUU -------162*4 -------- 648

Best wishes

[jarenchuatw]

Thanks…but still can’t really understand the 2nd part added on:


After 43x27=1161 rectangles have been For the width 166cm, there is a leftover of 166 - 27x6 = 4cm
Of which, 173/6 = 28 (round down) more rectangles can be cut.
Total = 1161 + 28 = 1189

Tot that we have already cut out some rectangles from 173, how come can still divide by 6 again??

[CRAZYBANANA]

jarenchuatw:

Thanks...but still can't really understand the 2nd part added on:


After 43x27=1161 rectangles have been For the width 166cm, there is a leftover of 166 - 27x6 = 4cm
Of which, 173/6 = 28 (round down) more rectangles can be cut.
Total = 1161 + 28 = 1189

Tot that we have already cut out some rectangles from 173, how come can still divide by 6 again??

Ya! Since the 173cm side has been cut into 43pc x4cm, then balance is only 1cm, cannot use liao! :?

[small]

Please help and TIA


Questions:
Three groups of pupils, A, B and C, worked on a project at different stages. Group B worked on the project during the first 4 days. Group A and C the n took over and worked together for the next 6 days.After which, Group A was left to complete the remaining work in 9 days. In this arrangement, Group B did 1/3 as much work as Group A while Group C did twice as much as Group B. How long will each group take to do the project without the involvement of other groups?

[speedmaths.012624com]

small:

Please help and TIA


Questions:
Three groups of pupils, A, B and C, worked on a project at different stages. Group B worked on the project during the first 4 days. Group A and C then took over and worked together for the next 6 days.After which, Group A was left to complete the remaining work in 9 days. In this arrangement, Group B did 1/3 as much work as Group A while Group C did twice as much as Group B. How long will each group take to do the project without the involvement of other groups?

Hi,

One possible method of solving this (without using any fractions in the working):

Let the ratio of work done by A:B:C be 3:1:2;
Total work to be done is 3 + 1 + 2 = 6 units.

[Group B did 1/3 as much work as Group A, while Group C did twice as much as Group B.]

Group A worked for 6 + 9 = 15 days.
Group B worked for 4 days.
Group C worked for 6 days.

Group A took 15 days to complete 3 units.
Group A will take 30 days to complete 6 units.

Group B took 4 days to complete 1 unit.
Group B will take 24 days to complete 6 units.

Group C took 6 days to complete 2 units.
Group C will take 18 days to complete 6 units.

Hope this helps.

Cheers


speedmaths.com


.

[small]

speedmaths.com:

small:

Please help and TIA


Questions:
Three groups of pupils, A, B and C, worked on a project at different stages. Group B worked on the project during the first 4 days. Group A and C then took over and worked together for the next 6 days.After which, Group A was left to complete the remaining work in 9 days. In this arrangement, Group B did 1/3 as much work as Group A while Group C did twice as much as Group B. How long will each group take to do the project without the involvement of other groups?

Hi,

One possible method of solving this (without using any fractions in the working):

Let the ratio of work done by A:B:C be 3:1:2;
Total work to be done is 3 + 1 + 2 = 6 units.

[Group B did 1/3 as much work as Group A, while Group C did twice as much as Group B.]

Group A worked for 6 + 9 = 15 days.
Group B worked for 4 days.
Group C worked for 6 days.

Group A took 15 days to complete 3 units.
Group A will take 30 days to complete 6 units.

Group B took 4 days to complete 1 unit.
Group B will take 24 days to complete 6 units.

Group C took 6 days to complete 2 units.
Group C will take 18 days to complete 6 units.

Hope this helps.

Cheers


speedmaths.com


.

Hi speedmaths.com,
Thank you very much... :thankyou:

[lousymum]

Hi,

Need help.
If Ahmad and Ben work together, they can complete a job in 12 days.
If Ahmad and Ben worked together for 3 days, followed by Ben who worked along for the newxt 5 days, they can finish 5/12 of the job.
How many days will each of them need to complete the job if they were to work alond?
Thanks.