## Claire4christ 3 years ago Example A jeweler is using an alloy, a mixture of metals. He has 10 pounds of the alloy. 2% is the rare metal robium. He has another source which is 5% robium. He wishes to combine these mixtures to form a mixture that is 3% robium. Solution: 1. Identify the variables. (0.02)(10) The quantity of robium in material 1 (5%)(x) The quantity of robium in material 2 (0.03)(x+10) The quantity of the desired mixture 2. Write an equation. 5% x + (0.02)(10) = (0.03)(x+10) The equation required. 3. Perform the Solution. 0.05x + 0.2 = .03x + 0.3 = 0.02x = 0.1 4. Write the answer. x = 5 The desired amount.

1. Claire4christ

And i need help with these problem. An alloy of tin is 15% tin and weighs 20 pounds. A second alloy is 10% tin. How much (to the nearest tenth lb.) of the second alloy must be added to the first alloy to get a 12% mixture. ______ pounds

2. Claire4christ

(0.15)(20) (10%)(x) (0.12)(x+20)

3. Claire4christ

so far right???

4. mikaa_toxica13

yess :)

5. Claire4christ

so next 10%x(0.15)(20)=(0.12)(x+20) right

6. mikaa_toxica13

yess. seems like you have it figured out.

7. Claire4christ

im confuse on last part

8. andriod09

What do you need now Claire?

9. Claire4christ

perform the solution

10. mikaa_toxica13

hrmmm i got .7 ?

11. andriod09

you mean solve the following: $.1x(.15)(.20)=(.12)(x+20)?$

12. Claire4christ

.10x+3=.12x+2.4=

13. andriod09

.10=.1 its 10, you don't need the 0, but it could be easier. to solve. $.1x+3=.12x+2.4$$.1x+.6=.12x$$.6=.11x$$x=1.833\infty(3)$

14. Claire4christ

so how did you get .6

15. andriod09

.06* my bad 1 sec. $.1x+.06=.12x$[\.06=.11x\]$1.833\infty(3)=x$ oddly,its the same answer.

16. Claire4christ

1.8 pounds???

17. andriod09

you could always use the percent bar method. that's easiest.

18. Claire4christ

so im confused how many pounds.

19. andriod09

A jeweler is using an alloy, a mixture of metals. He has 10 pounds of the alloy. 2% is the rare metal robium. He has another source which is 5% robium. He wishes to combine these mixtures to form a mixture that is 3% robium. |dw:1349373397808:dw|

20. Claire4christ

And i need help with these problem. An alloy of tin is 15% tin and weighs 20 pounds. A second alloy is 10% tin. How much (to the nearest tenth lb.) of the second alloy must be added to the first alloy to get a 12% mixture. ______ pounds

21. andriod09

i really hate percents just so you know. lol but ill help. just post ina new question, and don't forget to givethe best response medal.

22. Claire4christ

i will give bunch of them if you help me lol