18 kg of 15% copper and 72 kg of 60% copper should be combined by the metalworker to create 90 kg of 51% copper alloy.
<u>Step-by-step explanation:</u>
Let x = kg of 15% copper alloy
Let y = kg of 60% copper alloy
Since we need to create 90 kg of alloy we know:
x + y = 90
51% of 90 kg = 45.9 kg of copper
So we're interested in creating 45.9 kg of copper
We need some amount of 15% copper and some amount of 60% copper to create 45.9 kg of copper:
0.15x + 0.60y = 45.9
but
x + y = 90
x= 90 - y
substituting that value in for x
0.15(90 - y) + 0.60y = 45.9
13.5 - 0.15y + 0.60y = 45.9
0.45y = 32.4
y = 72
Substituting this y value to solve for x gives:
x + y = 90
x= 90-72
x=18
Therefore, in order to create 90kg of 51% alloy, we'd need 18 kg of 15% copper and 72 kg of 60% copper.
Answer:
As
1/4×100 = 0.25×100
= 25%
Thus,
1/4 = 25%
Step-by-step explanation:
Given the fraction
1/4
- In order to write the fraction 1/4 as a percent, all we need is to multiply 1/4 by 100.
i.e.
1/4×100 = 0.25×100
= 25%
Therefore, we conclude that:
1/4 = 25%
Answer:
51 pounds, 48 pounds, 44 pounds and 40 pounds in that chronological order.
