Hence first mechanic worked for 15 hours and second mechanic worked for 5 hours.
<h3>What is ratio and proportion?</h3>
When comparing two quantities of the same kind, ratio is utilized.
For two numbers, a and b, the ratio formula is written as a: b or a/b.
Two or more ratios are said to be in proportion if they are all equal.
Fractions are the foundation of the concepts of ratio and proportion.
Let x is the number of hours the first mechanic worked and y is the number of hours the second mechanic worked.
∵x+y = 20
x = 20 - y
115x+100y = 2225
115(20-y) + 100y = 2225
2300 - 115y +100y = 2225
15y = 75
y = 5 hours
∴ x = 20-5
x = 15 hours
To know more about ratio and proportion please visit:
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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
Answer:
Can't wait to learn geometry (shapes math) in a year or 1/2. This looks very interesting and mind blowing.
Step-by-step explanation:
it would right to left , my teacher had a little saying , Left is Less
You divide by -7 on both sides then add three to both sides and the answer is -3