Answer:
poop lol
Step-by-step explanation:
Zinc = 7/18
Divide 4.9 by 7 = 0.7
Multiply by 18 = 12.6
The answer is 12.6 lbs of alloy. Sorry if I'm wrong
ANSWER: 32 five-dollar bills
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EXPLANATION:
Let x be number of $5 bills
Let y be number of $10 bills
Since we have total of 38 bills, we must have the sum of x and y be 38
x + y = 38 (I)
Since the total amount deposited is $220, we must have the sum of 5x and 10y be 220 (x and y are just the "number of" their respective bills, so we multiply them by their value to get the total value):
5x + 10y = 220 (II)
System of equations:

Divide both sides of equation (II) by 5 so our numbers become smaller

Rearrange (I) to solve for y so that we can substitute into (II)

Substituting this into equation (II) for the y:

We have 32 five-dollar bills
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If we want to finish off the question, use y = 38 - x to figure out number of $10 bills

32 five-dollar bills and 6 ten-dollar bills
The next larger hundred is 5,100 .
The next smaller hundred is 4,900 .
5,000 is exactly midway between 4,900 and 5,100.
Neither of them is closer to 5,000 than the other one is.
So 5,000 is already rounded to the nearest hundred.
100 minus 95 equals 5
25 equals 5%
100 divided by 5 equals 20
20 times 25 equals 500
500 minus 25 equals 475
Answer:475 students present/ 500 students total in school