mariannu Group Title 6 oz of Pranav's Premium Coffee Blend was made by combining 2 oz of Arabica coffee beans which cost \$12/oz with 4 oz of robusta coffee beans which cost \$9/oz. Find the cost per oz of the mixture. SHow me how to do this so I will know how to do the other problems. one year ago one year ago

1. mariannu

I will gladly appreciate if you help. Thank you very much.

2. timo86m

\$12 oz * 2= arabica \$9 oz *4 = robusta arabica + robusta = pranav just plug in the w (\$12 oz * 2)+(\$9 oz *4 )= pranav

3. mariannu

hmmm my teacher uses the box and then he plugs it in like that. XD Do you know how to use the rectangular box version?

4. mariannu

|dw:1363159124065:dw|

5. mariannu

He plugs in the numbers in there and then he puts it into that equation you wrote.

6. mariannu

|dw:1363159165717:dw|

7. mariannu

C stands for cost /concentration and A is for amount

8. timo86m

|dw:1363159234819:dw| x can equal c*a which is cost

9. mariannu

I just want to know how you can plug in the box and transferring it into that equation. XD I forgot to add more detail to the drawing XD

10. timo86m

|dw:1363159271478:dw|

11. mariannu

How do you know which box to plug in the numbers? Like which number goes to which box square?

12. timo86m

maybe i am just guessing but you dont need the box the box is just a visual aid.

13. mariannu

|dw:1363159386553:dw|

14. mariannu

wel lI am more of a visual learner. :P XD

15. timo86m

|dw:1363159532318:dw|

16. mariannu

I got 60 as well. XD But its asking the cost per oz of mixture. So is it just 60?

17. mariannu

Or 10

18. timo86m

60/6=10 :)

19. mariannu

So then I am correct. XD

20. timo86m

yes :)

21. mariannu

Why did he have to make it complicated like that . may I ask you one more question for another math problem

22. mariannu

A chemist wants to mix 12 grams of 10 percent salt solution with some 75 percent salt solution to get a 20 percent salt solution. How many grams of the 75 percent salt solution are needed? I got an answer of 2.18

23. mariannu

or 2.48

24. timo86m

idk tho not 100 sure

25. mariannu

ok then thanks though I appreciate your help ^.^ I will figure out the rest on my own by examining the review I went over with m teacher thank you.

26. timo86m

btw i am wrong on that last one

27. timo86m

2.608695652 now i get

28. timo86m

1/120+2/(4*a) = (20/100) is formula