Q&A - P5 Math

[aps]

MathIzzzFun:

aps:

Dear all

Please help me with these two qns.

2)Richard, Dan and Tom shared a bag of marbles. Richard received 60 marbles and Tom received 25% less marbles than Dan. Later, Richard gave 28 marbles to be shared by Dan and Tom. As a result, Tom still has 25% fewer marbles than Dan and the number of marbles Dan receives increases by 40%. How many marbles were there in the bag?

Thanks!

At first,
Tom : Dan = 75:100 = 3:4 --> 15u : 20u -- total 35u

In the end,
Dan --> 20u x 7/5 = 28u
Tom --> 3/4 x 28u = 21u
Total 49u

49u-35u = 14u --> 28 , 1u --> 2

Total number of marbles --> 60 + 35 x 2 = 130

cheers.

Thank you very much! MathIzzzFun, you are great!

[gelfish]

Robert bought a total of 80 tables and chairs for $1780. When 20 chairs were given away, there were an equal number of tables and chairs left. if each table costs $6 more than each chair, find the cost of each chair.


I can solve it using algebra way. I know how to do it using the model way but i find it hard for the pupil to understand the model way. Can someone suggest how to explain using the model way? thanks

[bndreve]

Dear All,


pls help me with this qns. Thanks.

The ratio of Ahmad’s card to Benny’s card was 3:4. After Ahmad bought another 9 cards and Benny lost 18 cards, the ratio became 3:2. Find the total number of cards Ahmad and Benny had at first.

[Udon]

cimman:

Udon:

pls help...Thanks in advance.


Q1. In a Maths Olympiad, Team A and Team B each has an equal number of pupils. The total number of pupils in each team is less than 10. The average score of the pupils in Team A is 48 marks. The average score of the pupils in Team B is 62 marks. The total score of Team B is 42 marks more than that of Team A.

Find the number of pupils in each team.

here's another way of looking at the problem. I always start off with a table, it helps to organize the information in a useful way.
First you need to translate this sentence to an equation:
http://i47.tinypic.com/1dpmr.png\">
I call this the Difference Statement simply because it states the difference between 2 parameters. It is very common in problem sums.

Then fill up the table with information from the problem sum:

http://i45.tinypic.com/xkqedc.png\">

Next, circle the Difference Statement and fill in the blank boxes that was circled by using this Average formula:
Total/Quantity = Average
or
Total = Average x Quantity
http://i46.tinypic.com/iemu8l.png\">

You'll find that information in most Average problems will fit into this table nicely. Fill in the table, circle the equation, then solve the equation.

Hi Cimman,

Thanks for the illustration, I did the method with drawing a box and fix the number but come to calculation, I confused.... :?

Can this method apply to other problem sums?
How to teach my child to translate the question?

[cimman]

Udon:

cimman:

[quote=\"Udon\"]pls help...Thanks in advance.


Q1. In a Maths Olympiad, Team A and Team B each has an equal number of pupils. The total number of pupils in each team is less than 10. The average score of the pupils in Team A is 48 marks. The average score of the pupils in Team B is 62 marks. The total score of Team B is 42 marks more than that of Team A.

Find the number of pupils in each team.

here's another way of looking at the problem. I always start off with a table, it helps to organize the information in a useful way.
First you need to translate this sentence to an equation:
http://i47.tinypic.com/1dpmr.png\">
I call this the Difference Statement simply because it states the difference between 2 parameters. It is very common in problem sums.

Then fill up the table with information from the problem sum:

http://i45.tinypic.com/xkqedc.png\">

Next, circle the Difference Statement and fill in the blank boxes that was circled by using this Average formula:
Total/Quantity = Average
or
Total = Average x Quantity
http://i46.tinypic.com/iemu8l.png\">

You'll find that information in most Average problems will fit into this table nicely. Fill in the table, circle the equation, then solve the equation.

Hi Cimman,

Thanks for the illustration, I did the method with drawing a box and fix the number but come to calculation, I confused.... :?

Can this method apply to other problem sums?
How to teach my child to translate the question?[/quote]the Total Score for Team A is 48p because
Total = Quantity x Average, 48p = p x 48

same for Team B.
Questions can be translated by looking for keywords like average. You need to know what average represents, ie. total scores/number of pupils

[pineapple tarts]

Hello Maths guru,


Need your help on this question.

Mary bought 5 times as many cheese pie as apple pie for a party. She paid a total of $165. Each cheese pie costs twice as much as the apple pie. If each cheese pie costs $6, how many cheese pie and apple pie did she buy?

Thank you.

[pineapple tarts]

Hello again,


One more to trouble you guys.

In a school hall, a certain nos. of students can be arranged such that there are exactly 21 students per row. If the same nos. of students is arranged in rows of 16 students each, there will be 7 more rows and 8 students left over. How many students are there altogether?

Thank you in advance.

[MathIzzzFun]

pineapple tarts:

Hello again,


One more to trouble you guys.

In a school hall, a certain nos. of students can be arranged such that there are exactly 21 students per row. If the same nos. of students is arranged in rows of 16 students each, there will be 7 more rows and 8 students left over. How many students are there altogether?

Thank you in advance.

When arranged in rows of 16,
\"excess\" students from rows of 21 --> 16 x 7 + 8 = 120
these come from \"removing\" 5 from original rows of 21, so
rows of 21 --> 120/5 = 24

Number of students --> 24 x 21 = 504

cheers.

[MathIzzzFun]

pineapple tarts:

Hello Maths guru,


Need your help on this question.

Mary bought 5 times as many cheese pie as apple pie for a party. She paid a total of $165. Each cheese pie costs twice as much as the apple pie. If each cheese pie costs $6, how many cheese pie and apple pie did she buy?

Thank you.

Each cheese pie --> $6
Each apple pie --> $3
Cost of 1 group of 5 cheese pies + 1 apple pie
= 5 x $6 + $3 = $33

Number of groups --> $165/$33 = 5

Mary bought:
cheese pies --> 5 x 5 = 25
apple pies --> 5 x 1 = 5

cheers.

[pineapple tarts]

Dear MathIzzzFun


:thankyou: