Answer: Choice D
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Explanation:
The formula for the surface area of a cylinder is

We then replace r with 10 and h with 25. Keep in mind that the diameter is 20 mm, so the radius is half that at 10 mm.
So that's how we get to

three squared minus two thirds

three square = 3 x 3 = 9

Least common factor of 1 and 3 is 3

Three squared minus two third is twenty five by three.
Answer:
33/20
Step-by-step explanation:
1/12 - 1/15 = 5/60 - 4/60 = 1/60
d = 1/60
a_n = a_1 + d(n - 1)
a_11 = 1/15 + (1/60)(11 - 1)
a_11 = 1/15 + 1/6
a_11 = 4/60 + 10/60
a_11 = 14/60
a_11 = 7/30
a_12 = 14/60 + 1/60
a_12 = 15/60
a_12 = 1/4
s_n = n(a_1 + a_n)/2
s_11 = 11(1/15 + 7/30)/2
s_11 = 11(2/30 + 7/30)/2
s_11 = 11(9/30)/2
s_11 = 99/60
s_11 = 33/20
Let's begin by listing out the information given to us:
There are four students: n = 4
Number of students to be selected: r = 2
To calculate the combination of 2 students to be chosen, we use:

Therefore, there 12 possible combinations from these