The area of the semicircle is A = 1187.9 cm².
<h3>What is the area of a circle?</h3>
The area of a circle with a radius of r is A = πr².
Given that, the diameter of the semicircle is 55 cm.
The radius of the semicircle is,
r = 55/2
The area of a semicircle is given by,
A = (1/2)πr²
Substitute the values,
A = (1/2)π(55/2)²
A = 1187.9
Hence, the area of the semicircle is A = 1187.9 cm².
Learn more about the area of a circle:
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let h= history books
science books = s
h=2s there are 2 times as many history as science so to get them equal we double the science
h+s=81 there are 81 total history and science books
2s+s=81 substitute 2s for h in the above equation
3s = 81 combine like terms
s = 27
There are 27 science books
h=2s
h=2(27)
h=54
there are 54 history books
Answer:
31.82% probability that this day would be a winter day
Step-by-step explanation:
We use the conditional probability formula to solve this question. It is

In which
P(B|A) is the probability of event B happening, given that A happened.
is the probability of both A and B happening.
P(A) is the probability of A happening
In this question:
Event A: Rain
Event B: Winter day
Probability of rain:
0.42 of 0.25(winter), 0.23 of 0.25(spring), 0.16 of 0.25(summer) or 0.51 of 0.25(fall).
So

Intersection:
Rain on a winter day, which is 0.42 of 0.25. So

If you were told that on a particular day it was raining in Vancouver, what would be the probability that this day would be a winter day?

31.82% probability that this day would be a winter day
Answer:
Everything except 21/40. That is your ratio. The denominator always
Since x is the length, then x+7 has to be the width.
The area of a rectangle can be found via the formula :
A = length * width
So if we replace the area with the given number (170) and the length, and width, with what we assumed, we get..
170 = x * (x+7)
[which is.. ]
170 = x^2 +7x
0 = x^2 +7x - 170
And that is the answer.