Answer:
12
Step-by-step explanation:
2 times 8 is 16. 16 minus 4 is 12.
Sum of the First n Terms of a Geometric Sequence
Given a geometric sequence (or series) with a first-term a1 and common ratio r, the sum of the first n terms is given by:
We are given the series:
Before calculating the required sum, we need to find the common ratio. It's defined as the division of two consecutive terms. For example, using the first two terms:
The first term is a1 =120. Now apply the formula:
Operating:
Calculating:
Yes, the smaller the standard deviation the closer the results are clustered around the mean.
Standard deviations measure the spread of the values in a data set. The more spread out the values, the higher the standard deviation.
Answer:
117
Step-by-step explanation:
<DAB = <B + <C
Answer:
Siham ran for 305 minutes
Step-by-step explanation:
Let
Siham Ran for time = X
Siham Ran for time = X-60
According to given condition
X + (X-60) = 670
X + X - 60 = 670
2X = 670-60
2X = 610
X = 610/2
X = 305
So Siham ran for 305 minutes only