Let me reduce that to an equation for you:
10x + 80(1-x) = 30; solve for x.
Since the percentages of copper in the two components to be mixed are symmetric about the desired result, the answer is that the same amounts should be used. 600 ounces of the 30% copper.
900 ounces. Since this contains 20% copper, The copper content will be 180 ounces. The original 300 ounces contain 30% copper which is also 180 ounces. Hence in the resulting mixture of 1200 ounces (300+900), the total copper is 360 ounces (180+180). Hence the copper content of resulting mixture is 360/1200 which is 30%
Designate the weight in ounces of the first alloy, containing 40 percent copper, as w. Then, from the problem statement and the fact that percentages can be converted to decimals by dividing by 100, 0.40w + (0.80)(400) = 0.60(400 + w). Applying the usual methods of algebra, multiplying out results in: 0.40 w + 320 = 240 + 0.60w; transposing like terms with sign change and collecting results in: (0.40 - 0.60)w = 240 -320; or -0.20 w = -80, or w = 400.
the answer is alloy
Circulation-strike half dollars dated 1971 and later contain about 0.95 gm of nickel. The rest is copper, either in the pure copper core or mixed in the alloy used for the outer cladding. Older halves don't contain any nickel. Those dated 1965-70 are made of 40% silver and 60% copper, and halves (as well as dimes and quarters) dated 1964 and earlier are 90% silver alloy.
How much of an alloy that is 10% copper should be mixed with 400 ounces of an alloy that is 70% copper in order to get an alloy that is 20%
200 ounces.
Since the percentages of copper in the two components to be mixed are symmetric about the desired result, the answer is that the same amounts should be used. 600 ounces of the 30% copper.
LET X be the weigh tof the 20% alloy and then the total weight of the 30% alloy is 200 +X then 0.20X + .50 (200) = .30 (200 +X) .20X + 100 = 60 + .3X 40 = .1X 400 = X = 400 ounces
900 ounces. Since this contains 20% copper, The copper content will be 180 ounces. The original 300 ounces contain 30% copper which is also 180 ounces. Hence in the resulting mixture of 1200 ounces (300+900), the total copper is 360 ounces (180+180). Hence the copper content of resulting mixture is 360/1200 which is 30%
40 parts of 20 % plus 60 parts of 70 %
Designate the weight in ounces of the first alloy, containing 40 percent copper, as w. Then, from the problem statement and the fact that percentages can be converted to decimals by dividing by 100, 0.40w + (0.80)(400) = 0.60(400 + w). Applying the usual methods of algebra, multiplying out results in: 0.40 w + 320 = 240 + 0.60w; transposing like terms with sign change and collecting results in: (0.40 - 0.60)w = 240 -320; or -0.20 w = -80, or w = 400.
The mass or weight w of the desired 18 % copper alloy may be calculated from the masses of the two kinds of distinct alloys specified to be mixed and their masses, M for the copper-rich alloy and m for the lower copper alloy, from the formula 0.23M + 0.14m = 0.18 (M + m). Furthermore, M + m is stated to be 90, so that M = 90 - m. Therefore 0.23(90 - m) + 0.14m = 0.18 X 90 = 16.2. Multiplying out and collecting like terms results in 20.7 - (0.23 + 0.14)m = 16.2 or 0.09m = 4.5 or m = 50 ounces. M = 90 - 50 = 40 ounces.
By being mixed with zinc.
Brass is mainly an alloy of copper and zinc. Some alloys do have small amounts of arsenic added also.
The industrial name for a gold-copper alloy is Rose Goldor Tumbaga.If you also add silver to the alloy you get Electrum.
The question can be rewritten as the following equation: (20%x + 60%100)/(100+x) = 30% Where x is the amount of 20% copper you need to add. This equation can be solved by first multiplying both sides by (100+x) to get: 20%x + 60%100 = 30%100 + 30%x Now 30%100 can be subtracted from both sides 20%x + 30%100 = 30%x Now 20%x can be subtracted from both sides 30%100 = 10%x Now both sides can be divided by 10% 300 = x Thus you need to add 300 ounces of 20% copper alloy in order to get an alloy that totals 30% copper.