teach me how to solve P6 maths

[Narong Wongwan]

I am stumped though i could derive the answer but cant show the workings.

the pears and apples ratio is 7:5
after taking out 44 pears the ratio falls to 2:3
what is the total number of pears and apples?


i know answer is 144 but could not show the workings. i feel very stupid indeed.

 

[Thick Face Black Heart]

Let one unit be "x"

Before:
pears: 7x
apples: 5x

After:
pears: 7x-44
apples: 5x (same)

(7x-44)/5x = 2/3

Cross multiply:
3(7x-44) = 2(5x)
21x - 132 = 10x
11x = 132
x = 12

"Before" Total: 144
"After" Total: 144-44 = 100

 

[zhihau]

i know answer is 144 but could not show the workings. i feel very stupid indeed.

may like to use this as solution:

7:5 is 21p:15a
2:3 is 10p:15a
21p = 10p + 44
21p - 10p = 44
11p = 44
p = 4
21p = 21X4 = 84.
if there are a total of 84 pears, then there must be 84/7X5 apples = 60 apples.
therefore total number of fruits = 84 + 60 =144.

P6 only learn basic algebra, hope this helps.

 

[Clone]

I am stumped though i could derive the answer but cant show the workings.

the pears and apples ratio is 7:5
after taking out 44 pears the ratio falls to 2:3
what is the total number of pears and apples?


i know answer is 144 but could not show the workings. i feel very stupid indeed.

7:5 = 21:15
2:3 = 10:15

44 pears = 21-10 = 11 units
4 pears = 1 unit
21 + 15 = 36 units
4 X 36 units = 144 (ANS)

YAY! I passed my PSLE!

 

[Narong Wongwan]

its times like these i feel the tuition teachers fees are well earned. thank you.

 

[tonychat]

I am stumped though i could derive the answer but cant show the workings.

the pears and apples ratio is 7:5
after taking out 44 pears the ratio falls to 2:3
what is the total number of pears and apples?


i know answer is 144 but could not show the workings. i feel very stupid indeed.

you know the answer is 144 because the answer sheet is in front of you.. i feel very smart.

 

[tonychat]

the key of this question is the the number of pear has changed but not the apple in both situation.

so make the ratio of the apple before and after ( the pear has been removed) to be the same.

Then get the difference of the pear ratio ( before and after) and then find out 1 unit ratio represent how many pears.

Get the total units (36) of the pear and apple and multiple by 4 ( that is one unit = 4 pears)

The answer from your answer sheet is 144..

 

[Narong Wongwan]

you know the answer is 144 because the answer sheet is in front of you.. i feel very smart.

I take some consolation that 7 sms i sent out....none of them could solve it with logical workings....and one had to consult with his son. all tertiary educated including 3 that are qualified engineers.

 

[Cruxx]

may like to use this as solution:

7:5 is 21p:15a
2:3 is 10p:15a
21p = 10p + 44
21p - 10p = 44
11p = 44
p = 4
21p = 21X4 = 84.
if there are a total of 84 pears, then there must be 84/7X5 apples = 60 apples.
therefore total number of fruits = 84 + 60 =144.

P6 only learn basic algebra, hope this helps.

My method diff from 厚面黑心 but same as yours.

 

[Cruxx]

I take some consolation that 7 sms i sent out....none of them could solve it with logical workings....and one had to consult with his son. all tertiary educated including 3 that are qualified engineers.

You're serious? Pls tell me they aren't Sinkies. Don't let my low opinion of Sinkies plunge any further :(

 

[Narong Wongwan]

You're serious? Pls tell me they aren't Sinkies. Don't let my low opinion of Sinkies plunge any further :(

yes they are...one of them is a qualified pilot (kid you not)....
i admit i have always been weak in maths but at least i managed to passed all my PSLE, O and A levels maths prior to Uni but it is disgraceful i could not do present day PSLE maths.

 

[Clone]

My method diff from 厚面黑心 but same as yours.

Should be 厚脸黑心.

 

[middaydog]

solved with module method,


alamak, can not show it here:o

 

[Thick Face Black Heart]

yes they are...one of them is a qualified pilot (kid you not)....
i admit i have always been weak in maths but at least i managed to passed all my PSLE, O and A levels maths prior to Uni but it is disgraceful i could not do present day PSLE maths.

That's because the education system focusses on drilling rather than on developing a solid foundation.

Once you've learnt the basic skills of swimming, you will never forget. Our kids are not getting a real foundational education because our educators only want to cram as much material in as short a time span as possible. That's why our children end up being exam smart, but not able to connect the dots in real life.

That's only why you find yourself forgetting basic math even though you've been through A levels and even Uni.

The use of algebra to denote an unknown quantity in order to solve a problem is a basic skill. The understading of spatial relationships is another.

 

[zhihau]

but it is disgraceful i could not do present day PSLE maths.

don't despair, many find the P6 maths paper fast becoming another Maths Olympiad paper :o:o:o

 

[Thick Face Black Heart]

don't despair, many find the P6 maths paper fast becoming another Maths Olympiad paper :o:o:o

Nothing about math olympiad papers or difficult questions. Its a matter of foundation. The eductaion system is designed to drill and cram, not establish a solid foundation. That's why people can pass A levels and later forget to do PSLE math.

 

[Cruxx]

Should be 厚脸黑心.

Thanks 複製人

 

[zhihau]

The eductaion system is designed to drill and cram, not establish a solid foundation.

agree, the purpose of education is badly skewed. Minster Heng got hear you or not? :o:o:o

i find the quality of teachers dropping :(:(:(

 

[Thick Face Black Heart]

agree, the purpose of education is badly skewed. Minster Heng got hear you or not? :o:o:o

i find the quality of teachers dropping :(:(:(

I know. When pay is increasing but quality is dropping you know something is wrong. The good ones are not coming forward or are leaving the teaching profession early for a reason, and it little to do with pay.

 

[tanwahtiu]

When education become a profit making organisation to sell more books and get paid more they sold their souls to the devils. Who suffered the most? Children. Who wants to make more money? Uni grades like you end up causing more harm to your children.

That's because the education system focusses on drilling rather than on developing a solid foundation.

Once you've learnt the basic skills of swimming, you will never forget. Our kids are not getting a real foundational education because our educators only want to cram as much material in as short a time span as possible. That's why our children end up being exam smart, but not able to connect the dots in real life.

That's only why you find yourself forgetting basic math even though you've been through A levels and even Uni.

The use of algebra to denote an unknown quantity in order to solve a problem is a basic skill. The understading of spatial relationships is another.