An alloy is a mixture of metals. suppose that a certain alloy is made by mixing 50 grams of an alloy that 52% copper with 78 grams of pure copper. how many grams of copper are in the resulting mixture? what percent of the resulting mixture is copper?

See below in bold.

Step-by-step explanation:

The 50 grams of alloy contains 50 * 0.52 = 26 g of pure copper.

So the amount of copper n the mixture = 78 + 26 = 104 g.

The total mass of the mixture = 78 + 50 = 128 g.

% copper = 104 * 100 / 128

= 81.25%.

19.

step-by-step explanation:

you add the 9 in the tens column since it is a single digit and 9 plus zero is 9 so it is 19

10cm

step-by-step explanation:

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