Tutor MathsGuru: Ask me for your burning Maths questions!

[Suz855]

1) ratio of angsana tree to coconut tress was 1:4. When 30 coconut trees were chopped down to make way for an additional 25 angsana trees, the difference between the no. of angsana trees and coconut trees became 14. How many angsana trees were there in the beginning?



[][][][][]Angsana[][][][][] Coconut \t\t
B4\t\t\t1u\t\t4u
change\t\t\t+25\t\t-30
after\t\t\t1u+25\t\t4u-30

4u-30-1u-25 =14
3u =69
1u =23 (Angsana)

2) the ratio of the length of a rectangle to its breath is 5:7. If the perimeter is 48cm, find the area of the rectangle?

2x (5u+7u) =24u
24u–> 48
1u –> 2

Area of rect –> 10 x 14 = 140cm2

[MathIzzzFun]

Maize:

Hi Maths Guru


I am not able to solve this question given by my daughters school:I hope u can help!

\" After saving for a month, 1/5 of Heidi's savings was equal to 3/7 of Joseph's savings.
After Heidi spent $356 and Joseph saved an additional $428 , they had a n equal amount in their savings. How much did Heidi and Joseph save together in the end?\"

Hi

hope this helps

http://i51.tinypic.com/2r3v1qr.jpg\">

cheers.

[Maize]

MathIzzzFun:

Maize:

Hi Maths Guru


I am not able to solve this question given by my daughters school:I hope u can help!

\" After saving for a month, 1/5 of Heidi's savings was equal to 3/7 of Joseph's savings.
After Heidi spent $356 and Joseph saved an additional $428 , they had a n equal amount in their savings. How much did Heidi and Joseph save together in the end?\"

Thanks so much .. never knew it was so simple to solve.

[tinasen]

Pls help with this question.

84 students appeared for a test. 1/8 of the girls and 4/5 of the boys passed the test. If a total of 24 students passed the test, find the number of girls failed the test.

[MathIzzzFun]

Maize:

MathIzzzFun:

[quote=\"Maize\"]Hi Maths Guru


I am not able to solve this question given by my daughters school:I hope u can help!

\" After saving for a month, 1/5 of Heidi's savings was equal to 3/7 of Joseph's savings.
After Heidi spent $356 and Joseph saved an additional $428 , they had a n equal amount in their savings. How much did Heidi and Joseph save together in the end?\"

Thanks so much .. never knew it was so simple to solve.[/quote]u r welcome

cheers.

[MathIzzzFun]

tinasen:

Pls help with this question.

84 students appeared for a test. 1/8 of the girls and 4/5 of the boys passed the test. If a total of 24 students passed the test, find the number of girls failed the test.

Hi tinasen,

hope this helps

http://www.flickr.com/photos/62167097@N02/5921470837/in/photostream

cheers.

[TT2]

Hi, please help in this maths qn… Thank you.


There were some blue marbles and white marbles in a bag. If 70 blue marbles were to be removed from the bag, the ratio of the number of blue marbles to the number of white marbles would be 3:4. If 112 white marbles were to be removed from the bag instead, the ratio of the no. of blue marbles to the no. of white marbles would be 8:7. When 48 more blue marbles were to be added into the bag, what percentage of all the marbles would be blue marbles at last?

[Brenda10]

TT2:

Hi, please help in this maths qn... Thank you.


There were some blue marbles and white marbles in a bag. If 70 blue marbles were to be removed from the bag, the ratio of the number of blue marbles to the number of white marbles would be 3:4. If 112 white marbles were to be removed from the bag instead, the ratio of the no. of blue marbles to the no. of white marbles would be 8:7. When 48 more blue marbles were to be added into the bag, what percentage of all the marbles would be blue marbles at last?

Hi, extracted from dd's working:

B:W
3:4
+70 : -112
8:7

B 21 490 + 896 (3x7, 70x7, 112x8)
W 32 (4x8)
----------------------
11u ----1386

1u -----126
3u ----378
4u ----504


378 + 70 + 48 + 504 = 1000

378 + 70 + 48 = 496

496/1000 x 100 = 49.6%

Answer: 49.6%

Hopefully the above help.

[TT2]

Dear Brenda10,


That's very impressive. But we are not able to understand the steps. :nailbite: Why multiply by 7 and 8? Could your dd help to enlighten us? Thank you once again.

B 21 490 + 896 (3x7, 70x7, 112x8)
W 32 (4x8)

[Brenda10]

TT2:

Dear Brenda10,


That's very impressive. But we are not able to understand the steps. :nailbite: Why multiply by 7 and 8? Could your dd help to enlighten us? Thank you once again.

B 21 490 + 896 (3x7, 70x7, 112x8)
W 32 (4x8)

Hi TT2,

DD is usng \"External Change\" Concept.

http://i55.tinypic.com/n13vx5.jpg\">

x7 and x8 are due to nothing remains constant and way to solve is make the end (parts, that is 8:7) the same by using the principle of common multiple. We can use the comparison to find the qty representing the different in unit (that is 3:4).

You may refer onsponge Book 5 (Pg 80) or Challenging Maths Problems Made Easy (Pg 82) for more detail explanation.

Sorry as we are not good in explanation.