6
divide 80 by 4 to get 20
20 - 14 = 6
6 is the answer
If its multiplication sipmlest form is, 6/10
If its addition simplest form is, 7/9
If its any other just tell me! Hope i was right :p
Series is 15, 12, 9…,
Difference between terms is 3
By Arithmetic progression
a_{n}=a_{1}+(n-1)d
a_n = the nᵗʰ term in the sequence
a_1 = the first term in the sequence
d = the common difference between terms
So nth term is a(n) = 15 + (n-1)*3
= 15+ 3n -3
= 12 + 3n
1 out of 10 can be written as a fraction/ 1/10
Multiply total students by the fraction:
360 x 1/10 = 360/10 = 36
There are 36 left handed students.
Using it's concept, the standard deviation of the data is of 3.742.
<h3>What are the mean and the standard deviation of a data-set?</h3>
- The mean of a data-set is given by the <u>sum of all values in the data-set, divided by the number of values</u>.
- The standard deviation of a data-set is given by the square root of the <u>sum of the differences squared between each observation and the mean, divided by the number of values</u>.
For this data-set, the mean is:
M = (1 + 4 + 4 + 4 + 4 + 6 + 5)/7 = 4.
Hence the standard deviation is:

More can be learned about the standard deviation of a data-set at brainly.com/question/12180602
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