a)
his income must be "x" which is the 100%, and we would know that 0.2% of that is 12.37.

b)
his income must be "x" which is the 100%, and we would know that 2% of that is 12.37.

btw he's not making much either way.
Angle D is equal to Angle B because AB and DE are parallel to each other.
AD is a straight line so the (2) 2x angles and 72 degrees need to equal 180.
Setting up the equation you have:
2x + 2x + 72 = 180
Simplify:
4x + 72 = 180
Subtract 72 from each side:
4x = 108
Divide both sides by 4:
x = 108 / 4
x = 27
There are 4 boys and 12 students in total. It would be 4/12, but if it was to be simplified, it would be 1/3. The probability of a boy being selected is 1/3.
<h3>
Answer: 8</h3>
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Work Shown:

It will take 8 hours for the population to reach 196,608 bacteria.