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Ratio problem

Appreciate someone can help me solve this maths ratio problem. I thank you in advance.

Mr. bean has a carton containing some red and green apples. If he adds in 10 red apples, 0.6 of the number of apples in the carton will be green apples. If he adds in 30 green apples, 3/4 of the number of apples in the carton will be green apples. How many apples are there in the carton?
Reply 1
Do you know the answer to this question by any chance.
Reply 2
10=0.4 so therefore find out one part so 10/4 = 2.5
2.5*6=15
15+10=25
30+7.5=37.5 + 15 = 52.5

I'm not sure if that is right but this is what I think.
Reply 3
you have two unknowns (Number of red apples, number of green apples), and two equations, solve simultaneously and find the answer
Reply 4
10=0.4 so therefore find out one part so 10/4 = 2.5
2.5*6=15
15+10=25
2+3=5
5*3=15
15/6=2.5
2.5*12=30
15/2=7.5
30+7.5=37.5 + 15+2.5 = 55



I'm not sure if that is right but this is what I think.
Reply 5
Original post by delllboy
10=0.4 so therefore find out one part so 10/4 = 2.5
2.5*6=15
15+10=25
2+3=5
5*3=15
15/6=2.5
2.5*12=30
15/2=7.5
30+7.5=37.5 + 15+2.5 = 55



I'm not sure if that is right but this is what I think.


Can u explain what u have done here
30=0.75 so therefore find out one part so 30/4 = 18
2.5*6=15
15+10=25
8*31=248
d/dx (x+y)^2 = 2x+2y
18=96
4+3-4=3
e^ix= cosx + isinx
3+96+248+25+15+18 = 390
and 6=15 so you get = 52

I'm not sure if that is right but this is what I think.
Reply 7
Original post by MartinKellyisagod
30=0.75 so therefore find out one part so 30/4 = 18
2.5*6=15
15+10=25
8*31=248
d/dx (x+y)^2 = 2x+2y
18=96
4+3-4=3
e^ix= cosx + isinx
3+96+248+25+15+18 = 390
and 6=15 so you get = 52

I'm not sure if that is right but this is what I think.



This question involves cosx no way how is that even possible. This question look like a grade B question.
Reply 8
Original post by zed963
Can u explain what u have done here


30=0.75 so therefore find out one part so 30/4 = 18
2.5*6=15
15+10=25
8*31=248
d/dx (x+y)^2 = 2x+2y
18=96
4+3-4=3
e^ix= cosx + isinx
3+96+248+25+15+18 = 390
and 6=15 so you get = 52

pretty much this, i avoided differentiation by using drawing a hyperbolic function graph and simplifying it in my post to make it easier to see.

if you differentiate using the product rule with u=2.5 and v=4 giving dy/dx= u*dv/dx+v*du/dx then you will certainly arrive at your answer. the answer could be anywhere between 51.9 and 55 depending on how you rounded.

I'm not sure if that is right but this is what I think.
Reply 9
Trolls, everywhere..
Reply 10
Answer is 90 apples
Original post by delllboy
10=0.4 so therefore find out one part so 10/4 = 2.5
2.5*6=15
15+10=25
2+3=5
5*3=15
15/6=2.5
2.5*12=30
15/2=7.5
30+7.5=37.5 + 15+2.5 = 55



I'm not sure if that is right but this is what I think.



Original post by zed963
10=0.4 so therefore find out one part so 10/4 = 2.5
2.5*6=15
15+10=25
30+7.5=37.5 + 15 = 52.5

I'm not sure if that is right but this is what I think.



Original post by MartinKellyisagod
30=0.75 so therefore find out one part so 30/4 = 18
2.5*6=15
15+10=25
8*31=248
d/dx (x+y)^2 = 2x+2y
18=96
4+3-4=3
e^ix= cosx + isinx
3+96+248+25+15+18 = 390
and 6=15 so you get = 52

I'm not sure if that is right but this is what I think.


What is with everyone writing 30=0.75 and things like that? If you're going to write a full solution don't make it totally worthless and explain what you're doing. Why the hell euler's identity and differentiation is coming into this I have no idea. This is a GCSE-level question at most.

EDIT: I now realise that a couple of you are indeed trolling :tongue:


Original post by ng1804lim
Appreciate someone can help me solve this maths ratio problem. I thank you in advance.

Mr. bean has a carton containing some red and green apples. If he adds in 10 red apples, 0.6 of the number of apples in the carton will be green apples. If he adds in 30 green apples, 3/4 of the number of apples in the carton will be green apples. How many apples are there in the carton?


OP even though we don't regularly write full solutions I feel I may have to stop you getting confused from the above posts.

_________________________________

Right, OP, we can write the initial number of red apples as R and the initial number of green apples as G.

So to begin with we have a total number of R + G apples.

If we add 10 red apples, we now have (10 + R) + G apples, with 10 + R red apples and G green apples.

We know that 0.6*total apples = G so G = 0.6(10 + R + G) and then 0.4G = 0.6R + 6 - this is our first equation, we can make it look neater by multiplying by 5 to give 2G = 3R + 30

Then from the second part we now have R + (G + 30) apples - with R red apples and G + 30 green apples.

You are then told 0.75*total apples = G + 30 or: 0.75(R + G + 30) = G + 30

Rearranging that formula gives 0.25G = 0.75R - 7.5 multiply by 8 to give 2G = 6R - 60

So now we have 2 equations:

2G = 6R - 60 and 2G = 3R + 30

From this we know 6R - 60 = 3R + 30; 3R = 90, R = 30

Subbing this in either equation we get 2G = 120 and so G = 60 then finally R + G = 90
(edited 11 years ago)
Reply 12
Original post by hassi94
What is with everyone writing 30=0.75 and things like that? If you're going to write a full solution don't make it totally worthless and explain what you're doing. Why the hell euler's identity and differentiation is coming into this I have no idea. This is a GCSE-level question at most.

EDIT: I now realise that a couple of you are indeed trolling :tongue:




OP even though we don't regularly write full solutions I feel I may have to stop you getting confused from the above posts.

_________________________________

Right, OP, we can write the initial number of red apples as R and the initial number of green apples as G.

So to begin with we have a total number of R + G apples.

If we add 10 red apples, we now have (10 + R) + G apples, with 10 + R red apples and G green apples.

We know that 0.6*total apples = G so G = 0.6(10 + R + G) and then 0.4G = 0.6R + 6 - this is our first equation, we can make it look neater by multiplying by 5 to give 2G = 3R + 30

Then from the second part we now have R + (G + 30) apples - with R red apples and G + 30 green apples.

You are then told 0.75*total apples = G + 30 or: 0.75(R + G + 30) = G + 30

Rearranging that formula gives 0.25G = 0.75R - 7.5 multiply by 8 to give 2G = 6R - 60

So now we have 2 equations:

2G = 6R - 60 and 2G = 3R + 30

From this we know 6R - 60 = 3R + 30; 3R = 90, R = 30

Subbing this in either equation we get 2G = 120 and so G = 60 then finally R + G = 90


Thank you so much for the working
Give the original amounts a value R and G

adding 10 red gives R+10

How many in total now

What fraction = 0.6

etc
Original post by TenOfThem
Give the original amounts a value R and G

adding 10 red gives R+10

How many in total now

What fraction = 0.6

etc


Just an FYI; this is a duplicate of another thread where this has been answered (in the Maths, Science and Tech Academic Help Forum).
Original post by hassi94
Just an FYI; this is a duplicate of another thread where this has been answered (in the Maths, Science and Tech Academic Help Forum).


Ta

I will leave it then
Reply 16
Hi ng1804lim. Please don't make duplicate threads in different forums - I've merged the ones you made into this thread. Thanks!

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