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.
Process:
1. 21+24n= 7
2. 24n= 7 - 21
3. 24n= -14
Answ: n= -7/12
Answer:
21.6 or 22
Step-by-step explanation:
Triangles have same angles. This means that they are proportion.
50/27 = 40/x
when you cross multiply to solve x, 50x = 1080
so x = 21.6
If you have to nearest whole number, it will be 22
Answer:
4.83
Step-by-step explanation:
To find the circumference of a circle you need to take the diameter times Pi. So if you need to find the diameter from the circumference, simply divide the circumference by 3.14 which is Pi
Hope this helps!
