SOLUTION: An alloy is a mixture of metals. Suppose that a certain alloy is made by mixing 60 grams of an alloy that contains 18% copper with 100 grams of pure copper. a). How many grams

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Question 961657: An alloy is a mixture of metals. Suppose that a certain alloy is made by mixing 60 grams of an alloy that contains 18% copper with 100 grams of pure copper.
a). How many grams are in the resulting mixture? __grams.
b). What percentage of the resulting mixture is copper? ___%
Found 2 solutions by josmiceli, NeedTrigHelp:
Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
grams of copper in 18% alloy
-------------------
(a)
grams in resulting mixture
(b)

69.25% of the mixture is copper
check answer:
100 - 69.25 = 30.75% is NOT copper

30.75% is not copper
OK

Answer by NeedTrigHelp(2) (Show Source):
You can put this solution on YOUR website!
Computing a percent mixture
An alloy is a mixture of metals. Suppose that a certain alloy is made by mixing
60 grams of an alloy that contains 18% copper with 100 grams of pure copper.

Answer the questions below. Do not do any rounding.

(a) How many grams of copper are in the resulting mixture? ____ grams

(b) What percentage of the resulting mixture is copper? _____ %

_____________________________________________________________________________

A copper alloy is mixed with pure copper to create a new copper alloy.

There are 60 grams of the original copper alloy and it contains 18% copper.
There are 100 grams of pure (100%) copper.

(a) How many grams of copper are in the resulting mixture?

To find the amount of copper in the mixture, we first compute the amount of copper in each metal being mixed.

Amount of copper in the alloy: 18% of 60 grams = 0.18 (60) = 10.8 grams

Amount of copper in the pure copper: 100 grams

Then we add the amounts of copper in the metals being mixed.
10.8 grams +100 grams = 110.8 grams

So, there are 110.8 grams of copper in the resulting mixture.

___________________________________________________________________________________

(b) What percentage of the resulting mixture is copper?

The total amount of metal in the mixture is 60 grams +100 grams = 160 grams.

The total amount of copper in the mixture is 110.8 grams.

To determine what percentage of the mixture is copper, we first divide the total amount of copper by the total amount of metal.

Total amount of copper in mixture
____________________________ =
Total amount of metal in mixture

110.8 grams
___________ = 0.6925
160 grams

We then convert this to a percentage by multiplying by 100
(100) (0.6925) = 69.25%

So, 69.25% of the resulting mixture is copper.

___________________________________________________________________
Here is the final answer.

(a) How many grams of copper are in the resulting mixture? 110.8 grams

(b) What percentage of the resulting mixture is copper? 69.25%