Answer:
250 days.
Step-by-step explanation:
Let x represent number of days.
We have been given that of the 2,500 tons of ore mined daily at a quarry, 0.4 percent results in a certain pure metal.
Let us find the amount of pure metal by calculating 0.4% of 2500.



Amount of pure metal mined in x days will be
.
Since we need total pure metal production equal to 2500 ton, so we can set an equation as:



Therefore, it will take 250 days of mining for the total amount of pure metal produced at the quarry to be equal to the daily amount of ore mined.
<em>x</em> = amount invested at 8 %. Then 23 000 - <em>x</em> = amount invested at 9 %
Annual income (<em>I</em>) = interest at 8 % + interest at 9 %
<em>I</em> = 0.08<em>x</em> + 0.09(23 000 – <em>x</em>)
<em>I</em> = 0.08<em>x</em> + 2070 – 0.09<em>x</em>
<em>I</em> = 2070 – 0.01<em>x</em>
The kids in Class A are smarter than the kids in Class B
The value of x from the given diagram is 17
<h2>Vertically opposite angles</h2>
From the given diagram, m<2 and m<3 are vertically opposite since they form angles from the intersection of lines at the point X
Given that;
- m<2 = 4x + 2
- m<3 = 5x - 15
Equate both expressions to have:
m<2 = m<3
4x + 2 = 5x - 15
4x - 5x = -15 - 2
-x = -17
x = 17
Hence the value of x from the given diagram is 17.
Learn more on vertical angles here; brainly.com/question/1673457
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