Tutor MathsGuru: Ask me for your burning Maths questions!

[blessedami]

firebird:

Dear maths guru


Please help with the following P6 maths:
1) Mrs Chia baked 120 beef pies and chicken pies. After she gave away 1/4 of the beef pies and 2/5 of the chicken pies, she was left with 30 beef pies. How many chicken pies had she left?

2) The ratio of the number of yellow marbles to the total number of green and red marbles was 7:13. 40% of the marbles were red marbles. After throwing away 65 red marbles that were chipped, 20% of the remaining marbles were red. How many marbles were there left if another 24 green marbles were found to be chipped and thrown away?

3) Alicia gave some beads to Betty such that Betty had 40% of the number of beads that Alica had. After that, Alica gave another 170 beads to Betty. In the end, Betty had 80% of the number of beads that Alica had. How many beads did Betty have in the end?

4) There were 4 times as many boys as girls at a party at first. After 20 boys went home and 16 more girls joined in, there were 6 more boys than girls remaining at the party.
a) How many boys were there at the party initially?
b) How many children attended the party?

Thank you
Firebird

2)Y:G+R Total
7:13 20u
Since 40% of the marbles were red, the ratio for Red to Green plus Yellow will be

R:Y+G Total
40:60
=2:3 5u

Since in both cases, the total number of marbles is constant and so,

R: Y+G Total
2:3
=8:12 20u

Hence number of red marbles is 8 units, number of yellow marbles is 7 units and number of green marbles is 5 units.

When 65 red marbles were thrown away, the rest of the yellow and green marbles became 100%- 20%= 80%
Which is,
7u+5u= 12u
12u--->80%
So, 20%--->12u/4=3u
Remaining red marbles is 3u

8u-3u---->65
5u--->65
1u--->65/5= 13
3u+12u=15u
15u--->15x13=195

195-24=171

[blessedami]

firebird:

Dear maths guru


Please help with the following P6 maths:
1) Mrs Chia baked 120 beef pies and chicken pies. After she gave away 1/4 of the beef pies and 2/5 of the chicken pies, she was left with 30 beef pies. How many chicken pies had she left?

2) The ratio of the number of yellow marbles to the total number of green and red marbles was 7:13. 40% of the marbles were red marbles. After throwing away 65 red marbles that were chipped, 20% of the remaining marbles were red. How many marbles were there left if another 24 green marbles were found to be chipped and thrown away?

3) Alicia gave some beads to Betty such that Betty had 40% of the number of beads that Alica had. After that, Alica gave another 170 beads to Betty. In the end, Betty had 80% of the number of beads that Alica had. How many beads did Betty have in the end?

4) There were 4 times as many boys as girls at a party at first. After 20 boys went home and 16 more girls joined in, there were 6 more boys than girls remaining at the party.
a) How many boys were there at the party initially?
b) How many children attended the party?

Thank you
Firebird

3) After Alicia gave Betty beads for the first time, the ratio was

B:A
40:100
=2:5
Later, Alicia gave Betty another 170 beads. So,

B:A
2:5
+170 -170

80:100
=4:5

Let 2:5 be units and 4:5 be parts
2u+170=4p
5u-170=5p
So,1u-(170/5)= 1p

1u-34=1p
4u-(4x34)=4p
4u-136=4p
2u+170=4p
4u-2u=170+136
2u=306
1u=306/2=153
4u=4x153=612
4p=612-136=476
So, Betty has 476 beads left.

[liketoeat]

tianzhu:

liketoeat:

I've got this solution but didn't quite understand, could someone please explain to me...

Hi liketoeat
Hope this helps.

http://farm5.static.flickr.com/4141/4859699962_86def22625_b.jpg\">

Best wishes

wow, it's much better with diagram , you must have spent quite an awful lot of time doing it. I appreciate your hardwork very much . Thank you.

[liketoeat]

Brenda10:

liketoeat:

[quote=\"Brenda10\"]
Hi, I have come across the similar question.
However now I try to solve this question by following the previous sample I couldn’t get the answer same as you provided. I can only get (a) $17, (b) $113

That’s mean that I kept the wrong sample!! :!: Sorry not able to help and I also need to seek help from the rest.

I've got this solution but didn't quite understand, could someone please explain to me... thank you.

$4 + $6 = $10
$100 + $10 x 7 = $170

$170 / (3 + 7) = $17 (a)

$100 + $17 - $4 = $113 (b)

Hi Liketoboat

Paiseh. I am not good in explination :oops: but the following is my working step:

$4 + $6 = $10

1 Bag [ ]$10]
1 Belt [ ]

7 belts = 7 [ ]
3 bags = 3 [ ] + $30

10 [ ] = $100 - $30 = $70
1 [ ] = $7

$7 + $10 = $17
Each bag cost $17

Original amount : $100 + $7 + $6 = $113

Sorry unable to draw the model. This [ ] represent a rectangle model box[/quote]Thank you, Brenda10. Now, i understand.

[Brenda10]

liketoeat:

liketoeat:

Thank you, Brenda10. Now, i understand.

Hi Liketoeat

You're most welcome. We learn together. :celebrate:

[tianzhu]

liketoeat:

wow, it's much better with diagram , you must have spent quite an awful lot of time doing it. I appreciate your hardwork very much . Thank you.

Hi liketoeat

You're welcome.I am glad you liked it.

Best wishes

[blessedami]

firebird:

Dear maths guru


Please help with the following P6 maths:
1) Mrs Chia baked 120 beef pies and chicken pies. After she gave away 1/4 of the beef pies and 2/5 of the chicken pies, she was left with 30 beef pies. How many chicken pies had she left?

2) The ratio of the number of yellow marbles to the total number of green and red marbles was 7:13. 40% of the marbles were red marbles. After throwing away 65 red marbles that were chipped, 20% of the remaining marbles were red. How many marbles were there left if another 24 green marbles were found to be chipped and thrown away?

3) Alicia gave some beads to Betty such that Betty had 40% of the number of beads that Alica had. After that, Alica gave another 170 beads to Betty. In the end, Betty had 80% of the number of beads that Alica had. How many beads did Betty have in the end?

4) There were 4 times as many boys as girls at a party at first. After 20 boys went home and 16 more girls joined in, there were 6 more boys than girls remaining at the party.
a) How many boys were there at the party initially?
b) How many children attended the party?

Thank you
Firebird

4) Since 20 boys left and 16 girls joined, the diferrence between boys and girls decreased be 16+20=36.

After that the number of boys was still greater than the number of girls by 6.So initially, the difference was 36+6=42

Boys [][][][]
Girls [][ 42]

4u -1u = 3u
3u---->42
1u---->42/3=14
4u---->4x14=56

total--->5x14=70

[firebird]

Dear blessedami


Good afternoon.

Thank you very much for your answer.

With best regards
firebird

[kancheongmum]

Hi tianzhu


Tang did not reply my post about marks will be deducted for writing statemt like this
10.00 am + 2hrs = 12.00pm
my ds has been writing like this and he is not marked wrong till now P6 already. Don’t trust the school teacher cos he doesn’t care. Please help tks.

[maths6a]

kancheongmum:

Hi tianzhu


Tang did not reply my post about marks will be deducted for writing statemt like this
10.00 am + 2hrs = 12.00pm
my ds has been writing like this and he is not marked wrong till now P6 already. Don't trust the school teacher cos he doesn't care. Please help tks.

example:
2hr
3 pm ------arrow 5 pm
you will be penalised if you use the plus and minus sign when writing time duration.

3 hours + 5 hours = 8 hours is ok

Yes nowadays, situation getting from bad to worse.
I have students who told me teachers said it was wrong to label the arrows on parallellograms when you draw the construction.

(p + 5)/2 is marked wrong and told to write (p - 1)/2 + 3
Any comments?