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
X should be 7 after doing all the calculation.
Answer:
shoot, sorry but I don't know
Suppose that the farmer had bought the rice at x dollars per bag and had sold them at a 25% markup. How much did the bags cost him before he added the markup? 1.25x =$75 results in $75/1.25, or $60 per bag.
If he sold 25 bags, his profit would be 1.25($60/bag)(25 bags) = $1875.
I very seriously doubt that the rice was $7500 per bag. Perhaps you meant $75/bag...?