Help in math prob P5

[Thaiyotakamli]

There were 2/5 as many boys as girls at carnival at first. After 42 boys and 42 girls added, ratio become 3/4 as many boys as girls. How many boys were at the carnival at first?

 

Please dont give me algebra answer as P5 havent learn yet and i think answer must be done in ratio way.

Please help bros, thanks

[VellfireS]

There were 2/5 as many boys as girls at carnival at first. After 42 boys and 42 girls added, ratio become 3/4 as many boys as girls. How many boys were at the carnival at first?

 

Please dont give me algebra answer as P5 havent learn yet and i think answer must be done in ratio way.

Please help bros, thanks

 

So at first.. boys : 40% and 60% : girls

40% + 42 = boys

60% + 42 = girls..

So new figure :

 

wait.. I dont get the second part..

 

 

[Thaiyotakamli]

So at first.. boys : 40% and 60% : girls

40% + 42 = boys

60% + 42 = girls..

So new figure :

 

wait.. I dont get the second part..

After add 42 to each boys and girls, ratio become 3/4

[Vinfang]

There were 2/5 as many boys as girls at carnival at first. After 42 boys and 42 girls added, ratio become 3/4 as many boys as girls. How many boys were at the carnival at first?

 

Please dont give me algebra answer as P5 havent learn yet and i think answer must be done in ratio way.

Please help bros, thanks

 

This is a unit n part question (similar to simalteaous equations ).

2u + 42 = 3p => 8u + 168 = 12p

5u + 42 = 4p => 15u + 126 = 12p

 

8u + 168 = 15u + 126

7u = 42

1u = 6

 

12 boys at carnival at first. Is my answer correct?

 

[Thaiyotakamli]

This is a unit n part question (similar to simalteaous equations ).

2u + 42 = 3p => 8u + 168 = 12p

5u + 42 = 4p => 15u + 126 = 12p

 

8u + 168 = 15u + 126

7u = 42

1u = 6

 

12 boys at carnival at first. Is my answer correct?

Ok u r right, let me use ur way hahha seeking permission for copyright. Thanks :)

[Vinfang]

Ok u r right, let me use ur way hahha seeking permission for copyright. Thanks :)

 

Using model and branching methods are another alternative ways to solve it .... some school are teaching these methods.

Our children are getting tougher heuristic questions nowadays ... P6 work problems are even more challenging

 

Cheers man

[JumpySpeedFiend]

Initial:

B [iIIII][iIIII]

G [iIIII][iIIII][iIIII][iIIII][iIIII]

 

After 42 added:

B [iIIII][iIIII][-----------42----------]

G [iIIII][iIIII][iIIII][iIIII][iIIII][-----------42----------]

 

Remove 3p from Boy, we left 42 - 1p and remove 4p from Girl, we left 42 + 1p

 

We now have 42 - 1p / 42 + 1p = 3 / 4

 

expanding 3 / 4 to the ratio with a denominator closest to but larger than 42, we have 36 / 48.

 

36 / 48 is can be written as 42 - 6 / 42 + 6 and hence 1p is 6. Since number of boys at the start is 2p, answer is thus 12.

 

[Watwheels]

There were 2/5 as many boys as girls at carnival at first. After 42 boys and 42 girls added, ratio become 3/4 as many boys as girls. How many boys were at the carnival at first?

 

Please dont give me algebra answer as P5 havent learn yet and i think answer must be done in ratio way.

Please help bros, thanks

Wah...wait a sec. Isn't Algebra....ratio or fraction as in the same thing??

 

I'm confused.

[JumpySpeedFiend]

Wah...wait a sec. Isn't Algebra....ratio or fraction as in the same thing??

 

I'm confused.

 

Representing the same thing but it is the way to solve and tackle the questions that is different now.

 

During our era, we are just taught the algebra way so that we can pluck in the numbers, apply the arithmetic, and we get the answer.

 

Kids nowadays have to solve it by representing numbers, ratio in models, thought a visual method, apply the logic and solve it.

 

Answers will be the same, it is the approach that is different.

[Watwheels]

Representing the same thing but it is the way to solve and tackle the questions that is different now.

 

During our era, we are just taught the algebra way so that we can pluck in the numbers, apply the arithmetic, and we get the answer.

 

Kids nowadays have to solve it by representing numbers, ratio in models, thought a visual method, apply the logic and solve it.

 

Answers will be the same, it is the approach that is different.

I wish we were taught this way in the past. Less complex and less tedious in solving problems.

[Darryn]

Cannot be 12 - it doesn't work.

 

Why? at first had 5 units of girls, so 5 x 12 = 60

 

After add 42 had 4 units of girls, so 102 = 4 units of girls - 102 cannot divide evenly by 4 (they won't have "half" a girl")

 

[JumpySpeedFiend]

Cannot be 12 - it doesn't work.

 

Why? at first had 5 units of girls, so 5 x 12 = 60

 

After add 42 had 4 units of girls, so 102 = 4 units of girls - 102 cannot divide evenly by 4 (they won't have "half" a girl")

 

One unit is 6, not 12.

[Buffy]

Cannot be 12 - it doesn't work.

 

Why? at first had 5 units of girls, so 5 x 12 = 60

 

After add 42 had 4 units of girls, so 102 = 4 units of girls - 102 cannot divide evenly by 4 (they won't have "half" a girl")

 

 

Sorry juz for laugh.

 

But girl can have a choice of putting half ball.

[Puteh83]

now i really feel like my degree is not vital!!!

[Monxtre]

omg.. if i take Pr 5 math exam now confirm fail !

[Benlim]

There were 2/5 as many boys as girls at carnival at first. After 42 boys and 42 girls added, ratio become 3/4 as many boys as girls. How many boys were at the carnival at first?

 

Please dont give me algebra answer as P5 havent learn yet and i think answer must be done in ratio way.

Please help bros, thanks

Can you post the exact question? 2/5 is in fraction or is it in ratio? If in ratio you should use 2:5. Ditto for the 3/4.

[Haditan]

 

I use ratio and work in the following ways :

 

Before : B : G = 2 : 5 = 6 : 15

 

After : B : G = 3 : 4 = 6 : 8

 

 

Take the difference for the girl :

G : 7u = 42 ( 42 girls added )

1u = 6

 

So initially the boys will be 12 ( cos 2u).

 

Think for P5 , this way should be short and simple cos for their standard they are not suppose to solve in many steps or long workings.

 

 

 

[JumpySpeedFiend]

I use ratio and work in the following ways :

 

Before : B : G = 2 : 5 = 6 : 15

 

After : B : G = 3 : 4 = 6 : 8

 

 

Take the difference for the girl :

G : 7u = 42 ( 42 girls added )

1u = 6

 

So initially the boys will be 12 ( cos 2u).

 

Think for P5 , this way should be short and simple cos for their standard they are not suppose to solve in many steps or long workings.

 

This. Model answer.