Ok so you could use the equation h=t divided by w.
h represents the hours volunteered in one week.
t represents the amount of hours volunteered in the original amount of weeks.
w represents the original amount of weeks.
When you plug In the numbers you get h=72 divided by 12 which gives you h=6 so Penn volunteered 6 hours in one week.
You know the answer is reasonable because there are 168 hours in a week, so Penn could easily spend 6 hours a week volunteering.
Sorry if my explanation is confusing, but I tried to help. Good luck :)
<h3>
Answer: 10</h3>
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Explanation:
The two smaller triangles are proportional, which lets us set up this equation
5/n = n/15
Cross multiplying leads to
5*15 = n*n
n^2 = 75
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Apply the pythagorean theorem on the smaller triangle on top, or on the right.
a^2+b^2 = c^2
5^2+n^2 = m^2
25+75 = m^2
100 = m^2
m^2 = 100
m = sqrt(100)
m = 10
She can read 55 pages per hour
So, divide that by 2 to get 27.5
She can read 27.5 pages in the next 30 Min.
(She would be on page 137.5 :p)
Hope this helps!!
Do you have a better picture?