Mixture - Ounces Added

[Guest]

Another mixture:

120 ounces of an alloy is 60% pure silver. The alloy is to be 70% pure. Determine ounces of pure silver to be added.

Let x = oz. to be added.

120 oz. * 60% = 72 oz. of pure silver in 60% alloy.

120 + x = oz. in 70% alloy.

I have the answer. I was trying to use a table to place the data, but I am confused on the names for the data, and what info goes in the table.

[Guest]

72 + x = 0.70(120 + x)

[Guest]

Thanks. Will you help me with organizing the chart ?

[Guest]

I assume you mean something like.....

Let P1 equal the percent silver in the original product
Let P2 equal the percent silver in the final product
Let X equal the ounces of pure silver added


Re-write the equation to..... (P1(120) + X) = P2(120 + x)

Re-arrange to .... (P1(120) + X) / (120 + X) = P2

For this question where P1 = 60% = 0.6 and orig amount is 120 ounces, this becomes ......

(72 + X) / (120 + X) = P2

Make up a table for this equation for from X = 1 to say X=50 ounces silver and work out P2 for each value of X.

Silver added Percent Silver in Product

1 60.33
2 60.66
3 60.98
:: ::
20 65.71
and so on up to X = 39 to see how it fits the question
39 69.81
40 70.00 ....this is the answer to this question
:: ::
keep on doing this depending how big you want the table.

If you don't want to work out all the points for a lookup table you could draw a graph

The equation is not linear (straight line) but it is very near straight over a short range

Work out 3 or 4 points spread over the range and draw a best line fit
If you have Microsoft Excel it will do it easily.

[Guest]

I don't understand.

I have Excel and WordPerfect but I am not sure how to set up the problem.

[Guest]

This was meant to look like an example of the table but the spaces are not shown when posted on web.

The table has 2 columns "Silver added" and "Percent Silver in Product"
The 1 , 2 , 3, 20, 39, 40 are the rows in the table one for each ounce added, put this in 1st column
The 60.33, 60.66, 60.98, ::, 65.71, 69.81, 70.00 are the corresponding results of working out the formula for each ounce added, put these in the 2nd column.
Make the table as many rows as you want, You can then look up the table against the ounces added and see the percentage or lookup up a percentage and see how much to add.

Silver added Percent Silver in Product

1 60.33
2 60.66
3 60.98
:: ::
20 65.71
and so on up to X = 39 to see how it fits the question
39 69.81
40 70.00 ....this is the answer to this question
:: ::
keep on doing this depending how big you want the table.

For Excel all you need is to put the formula in a cell in one column and the numbers 1, 2,3,4,5,6,7,8,etc etc etc in cells in an adjacent column
and copy the formula down alongside the numbers and it will work out the percent against each number.
This is the formula.... (72 + X) / (120 + X) where X is 1,2,3,4,5,6,7,8 etc etc etc

[Guest]

Thanks.

[Guest]

It doesn't work.

[Guest]

What doesn't work.......I have just done it.

[Guest]

"put the formula in a cell in one column " Doesn't work.

" numbers 1, 2,3,4,5,6,7,8,etc etc etc in an adjacent colum " Doesn't work.

[Guest]

For Excel all you need is to put the formula in a cell in one column and the numbers 1, 2,3,4,5,6,7,8,etc etc etc in cells in an adjacent columnand copy the formula down alongside the numbers and it will work out the percent against each number.This is the formula.... (72 + X) / (120 + X) where X is 1,2,3,4,5,6,7,8 etc etc etc.

Ok, I will list what you need to put in the cells......

Put "Silver Added" in cell A1
Put "Percent Silver" in cell B1
Put the number 1 in cell A2
Put the formula =(72 + A2) / (120 + A2) in cell B2 ....Note.... remember the = sign ....
Put the number 2 in in cell A3
Copy the cell B2 and paste to B3

The cell B2 should read 0.603305785
The cell B3 should read 0.606557377

If you want you can format the B column cells to 2 decimal places and multiply column B by 100 so as to read in percentages rather than numbers.

To complete the table fill down column A with the numbers 3, 4,5,6,7,8,9, up to wherever, say 50 to give a consecutive list of 1 to 50 ounces silver added and then copy the formula in B3 down the B column alongside the list of numbers.

And all the percentages should be worked out for each number of ounces added
and you should see that when 40 ounces added this gives a percent of 0.7 OR 70%
this answers the question here......

You can then select the table and insert a line graph and see it in graph form.
If this does not work for you you need to read the help in Excel.

[Guest]

Thanks for the information.


" Put "Silver Added" in cell A1
Put "Percent Silver" in cell B1
Put the number 1 in cell A2
Put the formula =(72 + A2) / (120 + A2) in cell B2 ....Note.... remember the = sign ....
Put the number 2 in in cell A3
Copy the cell B2 and paste to B3

The cell B2 should read 0.603305785
The cell B3 should read 0.606557377 " I have this.

I have to manually add the numbers and formula each time from here.

[Guest]

No, you can use the excel fill down to fill the A column with a list of incrementing numbers
And just copy the formula down the B columns. I have relative address A1 A2 A3 etc so they will increment automatically as copied

Yes, you can add them manually, but it is tedious..????

Did it work?......for what you did so far?

[Guest]

No, having to manually add.

[Guest]

Do you mean the copy and paste did not work..??
You say you have Excel.....I mean Excel Spreadsheet.....as in MIcrosoft Excel spreadsheet.
What we are doing here is so basic it can be done on any spreadsheet.....Entering data in cells and copy and paste are the most basic functions.
You should read the help on Excel. OR Google excel operations on the web.
There are 2 operations you need to know about, Fill down and Copy cells

For fill down......you have already 1 and 2 entered in cells A2 and A3. Click on A2, hold shiftkey and click on A2, both A2 and A3 are highlighted. Notice there is a small square in bottom right of the highlighted box, click and hold left mouse on this and drag down until you come to cell A60, let go the left mouse and the cells should be filled with numbers from 1 to 58.......that is all your list of ounces added.

To copy a cell, you click on the cell, click copy, go to the cell where you want to copy to click on that cell and click paste.

If as you want to do copy cell B3 to Cells B4 down to say B60. You click on B3, click copy, Click on B4 and goto B60, hold shiftkey and click in B60. The cells B4 to B60 should be highlighted, now click paste, and the formula will be copied to all of B4 to B60

If you read the help this is all explained and also methods of doing this using the menus

These are the most basic operations in excel so if you cannot do these you will not be able to do anything on excel.
Start practicing with a few numbers say 1 to 10, then enter a formula to multiply each number by 2 and see do you get a list of the numbers in one column and the numbers times 2 in the column beside it. You should only need to manually enter the top 2 rows of the table and then fill down the numbers 1 to 10 in one column and then copy the formula down a column alongside them. and all the answers should be there.

[Guest]

Fill down does nothing- Will not drag down.

I give up.

[Guest]

Thanks anyway.

[Guest]

Did you read the help for filling cells with data....
Depending on the version of Excel, some versions work slightly differently.......
In some versions Fill down may not increment the numbers but should fill the list with the same number as is at the top of the list.

If you use the menu it may work better...and there are other options such as "fill series" where you specify the step or increment and the value to stop at.

Fill Series............you have already 1 and 2 entered in cells A2 and A3.
Click on A3, Find "Fill" on the menu, find the option "Series", a window should open with options to pick, Click on columns, step value...enter 1, Stop value....enter 60, click OK, and the column A should fill with the numbers 1 up to 60.

To copy of the formula is just a simple copy of the formula cell to any selected or highlighted range of cells.
Click on B3, click copy, click on B4, hold left mouse and drag down the B column to beside the number 60 in A column, release the left mouse, the formulas should copy down and all the percentages worked out.

[Guest]

Sorry, I left out a step..........

Click on B3, click copy, click on B4, hold left mouse and drag down the B column to beside the number 60 in A column, release the left mouse, Click Paste, the formulas should copy down and all the percentages worked out.

[Guest]

I have Excel Starter. The "Fill Series" worked.

Thanks again for the helpful info.