An = a1 * r^(n-1)
-405 = -5*3^(n-1)
3^(n-1) = 81
3^4 = 81 so n-1 = 3 and n = 4
Sn = S4 = -5 (1 - 3^4) / ( 1 - 3) = 400 / -2 = -200 Answer
I have memorized facts about fractions like these, so can tell you ...

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A fraction with 9 as a denominator is a repeating 1-digit decimal with the decimal digit being the numerator of the fraction.
A fraction with 11 as a denominator is a repeating 2-digit decimal with the two digits being 9 times the numerator of the fraction.
1/8 = 0.125, so any multiple of 1/8 is that multiple of 0.125.
Answer:
It is <em>a</em> solution, one of an infinite number of solutions.
Step-by-step explanation:
You can check to see if the given point is in the solution set:
4(-4) +5(4) = -16 +20 = 4 > -6 . . . . yes
-2(-4) +7(4) = 8 +28 = 36 > 20 . . . yes
The offered point satisfies both inequalities, so is in the solution set. It is not <em>the</em> solution, but is one of an infinite number of solutions.
Answer:
The answer is B) 72
Step-by-step explanation:
find the bigger arc: 360 - 108 = 252
x = 252 - 108/2
x = 144/2
x = 72