Q&A - P5 Math
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![](\"http://i49.tinypic.com/2zinaco.jpg\")
http://i49.tinypic.com/2zinaco.jpg\">
Pl help :? -
Jamesbond:
Pl help :?
Shaded part is 5/8 of the square.
Therefore answer is 240 x (5/8) = 150 cm square.
Explanation:
We know that AP = PB and AQ = QD.
Therefore, it is clear that the square can be divided into 4 equal small squares, which can then be cut up into 8 small triangles.
It should be obvious from the drawing that half of APXQ is shaded where X is the center point of the square.
Also, it should be obvious that the other 2 shaded triangles FBC and QDC can be pieced together to form a rectangle that is half of the entire square.
Therefore, out of the 8 small triangles, we have 6 shaded triangles. -
[quote]2. Mary spent $270 on a necklace. She spent 1/7 of her money on a dress. She then had 3/8 of her money left. How much money did she have at first?[/quote]
It might be good to draw the model for this question (if you have trouble visualizing) although I am not going to provide one in the following solution.
After spending $270, Mary has some money left. Let us call that the remainder.
She then spent 1/7 of the remainder on a dress.
Thereafter, she is left with 6/7 of the remainder.
Therefore, 6/7 of remainder = 3/8 of her total money
For reasonable comparison, you need the unit size to be the same!
As such, find the lowest common multiple of 6 and 3. Then make the numerator the same (same amount represented by the same number of units -> units are of the same size), i.e.
6/7 of remainder = 6/16 of her total money
As such, her total money can be represented using 16 units. The remainder is then represented using 7 units.
The money spent on the necklace is hence represented by
16 - 7 = 9 units
9 units = $270
1 unit = $270 / 9 = $30
16 units = $30 x 16 = $480 -
ChewingPencilLine:
[quote]2. Mary spent $270 on a necklace. She spent 1/7 of her money on a dress. She then had 3/8 of her money left. How much money did she have at first?
It might be good to draw the model for this question (if you have trouble visualizing) although I am not going to provide one in the following solution.
After spending $270, Mary has some money left. Let us call that the remainder.
She then spent 1/7 of the remainder on a dress.
Thereafter, she is left with 6/7 of the remainder.
Therefore, 6/7 of remainder = 3/8 of her total money
For reasonable comparison, you need the unit size to be the same!
As such, find the lowest common multiple of 6 and 3. Then make the numerator the same (same amount represented by the same number of units -> units are of the same size), i.e.
6/7 of remainder = 6/16 of her total money
As such, her total money can be represented using 16 units. The remainder is then represented using 7 units.
The money spent on the necklace is hence represented by
16 - 7 = 9 units
9 units = $270
1 unit = $270 / 9 = $30
16 units = $30 x 16 = $480[/quote]Hi, Sorry to interrupt..She only spent 1/7 of the money on the dress and not the remainder. So the steps are
1/7=8/56
3/8=21/56
21/56+8/56=29/56
56-29=27
270/27=10
56*10=560
Correct me if I am wrong. -
ChewingPencilLine:
Got it...Thank you..Jamesbond:
Pl help :?
Shaded part is 5/8 of the square.
Therefore answer is 240 x (5/8) = 150 cm square.
Explanation:
We know that AP = PB and AQ = QD.
Therefore, it is clear that the square can be divided into 4 equal small squares, which can then be cut up into 8 small triangles.
It should be obvious from the drawing that half of APXQ is shaded where X is the center point of the square.
Also, it should be obvious that the other 2 shaded triangles FBC and QDC can be pieced together to form a rectangle that is half of the entire square.
Therefore, out of the 8 small triangles, we have 6 shaded triangles. -
Anna, Bee Bee and Cari shared the cost of a gift for their friend. 2/5 of Cari’s share was equal to 1/2 of Bee Bee’s and Anna’s share. 1/3 of Bee Bee share was equal to 1/3 of Cari and Anna share. If Anna paid $40 less than Cari, how much did the gift cost
Pls help -
Jamesbond:
Hi, Sorry to interrupt..She only spent 1/7 of the money on the dress and not the remainder. So the steps areChewingPencilLine:
[quote]2. Mary spent $270 on a necklace. She spent 1/7 of her money on a dress. She then had 3/8 of her money left. How much money did she have at first?
It might be good to draw the model for this question (if you have trouble visualizing) although I am not going to provide one in the following solution.
After spending $270, Mary has some money left. Let us call that the remainder.
She then spent 1/7 of the remainder on a dress.
Thereafter, she is left with 6/7 of the remainder.
Therefore, 6/7 of remainder = 3/8 of her total money
For reasonable comparison, you need the unit size to be the same!
As such, find the lowest common multiple of 6 and 3. Then make the numerator the same (same amount represented by the same number of units -> units are of the same size), i.e.
6/7 of remainder = 6/16 of her total money
As such, her total money can be represented using 16 units. The remainder is then represented using 7 units.
The money spent on the necklace is hence represented by
16 - 7 = 9 units
9 units = $270
1 unit = $270 / 9 = $30
16 units = $30 x 16 = $480
1/7=8/56
3/8=21/56
21/56+8/56=29/56
56-29=27
270/27=10
56*10=560
Correct me if I am wrong.[/quote]Oh my! I am so sorry! Misread the question, haha! I did not check if your workings are right (in a rush right now) but thank you very much for pointing out my mistake!!
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favianboy:
Hi moderatorsAnna, Bee Bee and Cari shared the cost of a gift for their friend. 2/5 of Cari's share was equal to 1/2 of Bee Bee's and Anna's share. 1/3 of Bee Bee share was equal to 1/3 of Cari and Anna share. If Anna paid $40 less than Cari, how much did the gift cost
Pls help
Please help to delete.
Best wishes -
Hi, I’m back again for support:
Henry, Robert and Wee Teck bought a present for their friend. Robert paid 1/3 of the amount paid by Henry and Wee Teck. Henry and Robert paid 2/3 of the amount paid by Wee Teck. Given that Wee Teck paid $27 more than Henry, how much did the present cost?
Thank you very much. -
Oracle:
Hi moderatorsHi, I'm back again for support:
Henry, Robert and Wee Teck bought a present for their friend. Robert paid 1/3 of the amount paid by Henry and Wee Teck. Henry and Robert paid 2/3 of the amount paid by Wee Teck. Given that Wee Teck paid $27 more than Henry, how much did the present cost?
Thank you very much.
Please help to delete.
Best wishes
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