Q&A - P5 Math

[happyheart]

Can someone help to explain please. Urgent, Thanks.


Minah bought some dolls at an average price of $34 each. She bought another 2 dolls for $58 each, the average price would be $40. How mNy dolls did she buy altogether? Ans: 6

[speedmaths.012624com]

happyheart:

Can someone help to explain please. Urgent, Thanks.


Minah bought some dolls at an average price of $34 each. She bought another 2 dolls for $58 each, the average price would be $40. How mNy dolls did she buy altogether? Ans: 6

Hi happyheart,

One possible method:

Look at the difference in the prices of the dolls bought and the average price:
Difference between $34 and $40 is $6.
Difference between $40 and $58 is $18.

The ratio of the price differences is $6:$18 or 1:3

The ratio of the number of dolls bought will be the reverse, or 3:1. or 6:2.
Minah bought 6 dolls for $34 each, and she bought 2 dolls for $58 each.

Total number of dolls bought is 6 + 2 = 8.

Hope this helps.

Cheers

speedmaths.com

PS
For parents who are keen to learn more about this method, they can come for our Parents' Workshop on 19 May - look for our thread under Happenings forum.
.

[happyheart]

speedmaths.com:

happyheart:

Can someone help to explain please. Urgent, Thanks.


Minah bought some dolls at an average price of $34 each. She bought another 2 dolls for $58 each, the average price would be $40. How mNy dolls did she buy altogether? Ans: 6

Hi happyheart,

One possible method:

Look at the difference in the prices of the dolls bought and the average price:
Difference between $34 and $40 is $6.
Difference between $40 and $58 is $18.

The ratio of the price differences is $6:$18 or 1:3

The ratio of the number of dolls bought will be the reverse, or 3:1. or 6:2.
Minah bought 6 dolls for $34 each, and she bought 2 dolls for $58 each.

Total number of dolls bought is 6 + 2 = 8.

Hope this helps.

Cheers

speedmaths.com

PS
For parents who are keen to learn more about this method, they can come for our Parents' Workshop on 19 May - look for our thread under Happenings
forum.
.

Thanks speedmaths! The correct answer is indeed 8 dolls, I typed in wrongly earlier.

[zeemimi]

speedmaths.com:

happyheart:

Can someone help to explain please. Urgent, Thanks.


Minah bought some dolls at an average price of $34 each. She bought another 2 dolls for $58 each, the average price would be $40. How mNy dolls did she buy altogether? Ans: 6

Hi happyheart,

One possible method:

Look at the difference in the prices of the dolls bought and the average price:
Difference between $34 and $40 is $6.
Difference between $40 and $58 is $18.

The ratio of the price differences is $6:$18 or 1:3

The ratio of the number of dolls bought will be the reverse, or 3:1. or 6:2.
Minah bought 6 dolls for $34 each, and she bought 2 dolls for $58 each.

Total number of dolls bought is 6 + 2 = 8.

Hope this helps.

Cheers

speedmaths.com

May i know if there is another method to solve this question? I don't understand the reason for taking the difference between 40 and 58. :?

[MathIzzzFun]

zeemimi:

speedmaths.com:

Can someone help to explain please. Urgent, Thanks.


Minah bought some dolls at an average price of $34 each. She bought another 2 dolls for $58 each, the average price would be $40. How mNy dolls did she buy altogether? Ans: 6

Hi happyheart,

One possible method:

Look at the difference in the prices of the dolls bought and the average price:
Difference between $34 and $40 is $6.
Difference between $40 and $58 is $18.

The ratio of the price differences is $6:$18 or 1:3

The ratio of the number of dolls bought will be the reverse, or 3:1. or 6:2.
Minah bought 6 dolls for $34 each, and she bought 2 dolls for $58 each.

Total number of dolls bought is 6 + 2 = 8.

Hope this helps.

Cheers

speedmaths.com

May i know if there is another method to solve this question? I don't understand the reason for taking the difference between 40 and 58. :?

Hi

http://i46.tinypic.com/2j624jr.png\">

cheers.

[zeemimi]

MathIzzzFun:

Hi

http://i46.tinypic.com/2j624jr.png\">

cheers.

thanks mathizzzfun. the picture makes everything clearer.

[MathIzzzFun]

zeemimi:

MathIzzzFun:

Hi

http://i46.tinypic.com/2j624jr.png\">

cheers.

thanks mathizzzfun. the picture makes everything clearer.

u r welcome

cheers.

[zico]

Thanks in advance to anyone who can help.


--------------------

Leela and Kumar shared a sum of money. Leela's share was $90 less than Kumar's. After Kumar gave 1/7 of his share to Leela, Leela had $10 more than Kumar.

(a) how much did Leela have at first?

(b) What was the sum of money?

[zico]

Thanks in advance to anyone who can help.


--------------------

Leela and Kumar shared a sum of money. Leela's share was $90 less than Kumar's. After Kumar gave 1/7 of his share to Leela, Leela had $10 more than Kumar.

(a) how much did Leela have at first?

(b) What was the sum of money?

[Suz855]

XxxxXxxleela. Kumar

Xxxxxxx7u-90 7u
Change+1u. -1u
8u-90. 6u

8u-90-6u=10
2u=100
1u=50
Leela at first 7x50-90=260
b) 260+350=610