Area of a circle is pi x r ^2
R = diameter/2
R = 1.8/2 = 0.9
Area = 3.142 x 0.9^2
Area = 2.5 square cm.
Answer:
Irrational
Step-by-step explanation:
The square root of 16.45 would be a number that will never end, making it irrational.
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.
4) 4m, 18, and g
5) 4n means 4xn
Mechanical Advantage = Force by Hammer / Force by Nail = 160/40 = 4
