6 - 34 + 96 - 384 +...
a 1 = 6 , a 2 = a 1 * ( - 4 ) , a 3 = a 2 * ( - 4 ), a 4 = a 3 * ( - 4)...
a 5 = - 384 * ( - 4 ) = 1,536
a 6 = 1536 * ( - 4 ) = - 6,144
a 7 = - 6,144 * ( - 4 ) = 24,576
This is a sum of a geometric sequence:
S 7 = 6 - 24 + 96 - 384 + 1,536 - 6,144 + 24,576 = 19,662
Another way to solve this:
S 7 = a 1 * ( r^n - 1) / ( r - 1 ) = 6 * (( - 4) ^7 - 1 )/ (- 4 - 1)=
= 6 * (-16,385) / (-5 ) = 19,662
Answer:
a. z-score = -1.2
b. The age 23 years old is -1.2 standard deviations below the mean
c. The age is not unusual
Step-by-step explanation:
a. Transformation to z-score
Mathematically;
z-score = (x - μ)/σ
where σ and μ are the standard deviation and the mean respectively.
From the question, x = 23, μ = 27.2 and σ = 3.5
Let’s put these into the equation;
z-score = (23-27.2)/3.5 = -1.2
b. Interpretation of result
The interpretation is that 23 years old is -1.2 standard deviations below the mean
c. Determination
The age is not unusual. This is because any z-value below -2 or above 2 is considered unusual
-1.2 is above -2 and thus it is not unusual
Pythagorean theorem - a^2 + b^2 = c^2
2^2+3^2 = d^2
d^2 = 13
d= square root of 13
Answer:
(1/2), (3/2)
Step-by-step explanation:
midpoint fomula
(x1+x2)/ 2, (y1+y2)/2
(5-4)= 1 1/2 = (1/2)
(-1+4)=3 3/2=(3/2)
4x+7=35
4x=28
x=7
A corresponding solution of the matching equation is a fancier way of telling you to find the number that represents x
