brzeczyszczyk

1 February 2012, 12:31:01

They seem to really have made it shorter. So - starting from your first line, the second one is - with the calculations in the brackets:
x/(52735+x)=0.25
So the next step - to get just x on the left:
x=0.25(52375+x)
Clear? You just multiply the right side with the amount in the brackets.
And now we do it further:
x=13183.75+0.25x
Now we group all x's on the left:
0.75x=13183.75
And to finish we try to get only x by dividing the right side with 0.75:
x=17578.33333333333333333...

That's how I see it.

They seem to really have made it shorter. So - starting from your first line, the second one is - with the calculations in the brackets: x/(52735+x)=0.25 So the next step - to get just x on the left: x=0.25(52375+x) Clear? You just multiply the right side with the amount in the brackets. And now we do it further: x=13183.75+0.25x Now we group all x's on the left: 0.75x=13183.75 And to finish we try to get only x by dividing the right side with 0.75: x=17578.33333333333333333... That's how I see it.

brzeczyszczyk

1 February 2012, 12:32:37

As to the question whether to use 0.25 or 1/4, of course it does not matter but you want to use something that makes it easy for you to calculate on a calculator, don't you? So 0.25 is easier.

And for the last question - it is just my expanded way condensed in one line.

As to the question whether to use 0.25 or 1/4, of course it does not matter but you want to use something that makes it easy for you to calculate on a calculator, don't you? So 0.25 is easier. And for the last question - it is just my expanded way condensed in one line.

ec1982

1 February 2012, 17:29:52

Thanks brzeczyszczyk - that makes things a lot clearer! But I still have a question about the 0.75. Your explanation says we need to group all x's on the left. So I can see one x before the = sign, and 0.25x after the + sign. How does this result in the 0.75x in the next step? If you had asked me I'd have written 0.25x+x instead.....?

The rest makes a lot more sense though thank you!

Thanks brzeczyszczyk - that makes things a lot clearer! But I still have a question about the 0.75. Your explanation says we need to group all x's on the left. So I can see one x before the = sign, and 0.25x after the + sign. How does this result in the 0.75x in the next step? If you had asked me I'd have written 0.25x+x instead.....? The rest makes a lot more sense though thank you!

soniapupaza

2 February 2012, 09:07:27

it is x-0.25x=13185.75
x (1-0.25)=13185.75

it is x-0.25x=13185.75 x (1-0.25)=13185.75

brzeczyszczyk

2 February 2012, 10:18:21

Well, it is just like that - if you have x=15+0.25x, then to solve the equation, you need to group the x's on one side and it become x-0.25x=15, then 0.75x=15, so x=15/0.75=20. I took an easy number to show it. Think of it like that: 6=4+2. If you want to move 2 on the other side, you have to substract it to make the equation true, don't you?

Sorry, I really do not know how to explain it - to me it seems quite obvious and so it is difficult to explain, heh.

Well, it is just like that - if you have x=15+0.25x, then to solve the equation, you need to group the x's on one side and it become x-0.25x=15, then 0.75x=15, so x=15/0.75=20. I took an easy number to show it. Think of it like that: 6=4+2. If you want to move 2 on the other side, you have to substract it to make the equation true, don't you? Sorry, I really do not know how to explain it - to me it seems quite obvious and so it is difficult to explain, heh.

ec1982

2 February 2012, 13:56:52

Aha so now I see - what I was looking for was to see where the number 0.75 comes from, and it is because you subtracct the 0.25 from 1 as soniapupaza has written it above. Thanks guys!! Finally I can get this kind of question right!

Aha so now I see - what I was looking for was to see where the number 0.75 comes from, and it is because you subtracct the 0.25 from 1 as soniapupaza has written it above. Thanks guys!! Finally I can get this kind of question right!