The answer is D. 13 Inches, this is 6th grade math I believe?
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:
Step-by-step explanation:
Area of a triangle is A=(1/2)*base*height
A = (1/2)*(4.4)*(3.3) = 0.726 cm2
There are 4 choose 3 ways to hold 3 kings and 4 possible queens to make up the fourth card of the hand out of a total of 54 choose 4 possible four-card hands, which gives us the following expression for the probability of being dealt 3 kings and a queen out of 4 cards: Or roughly 1 in every 16920 four card hands.
