Answer:
l=0.1401P\\
w =0.2801P
where P = perimeter
Step-by-step explanation:
Given that a window is in the form of a rectangle surmounted by a semicircle.
Perimeter of window =2l+\pid/2+w

Or 
To allow maximum light we must have maximum area
Area = area of rectangle + area of semi circle where rectangle width = diameter of semi circle


Hence we get maximum area when i derivative is 0
i.e. 

Dimensions can be

<span>The product of 7 and 0.04 is 0.28=true</span>
As fraction it would be 6/30 reduced 1/5 and as percentage 20% so 20% of the students were off.<span />
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
250-3m
m represents months
Not an equation but an expression since I don’t know the number of months he was on the diet.