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:
Given
Jar contains 15 Green and
15 Purple marbles
Total marble
Probability of Picking a Purple marble is
Therefore probability of picking a marble is 
Answer: 4 miles
Step-by-step explanation:
I would say yes because like a triangle isn’t a polygon pentagon octagon are polygons
Answer:
x = 15°
Step-by-step explanation:
<em><u>The segment is a diameter, So let us assume the part in which there lies the triangle as a semicircle.</u></em>
=> <em>A triangle inscribed in a semi-circle will always have one of its angle equal to 90</em>
=> <em>So the angle (not 75 and x) is 90 degrees.</em>
<em>=> To find the value of x, we'll subtract rest of the angles from 180 degrees (because the interior angles of a triangle add up to 180°)</em>
<em>So,</em>
=> x = 180-90-75
=> x = 15°
