12 times ten equals one hundred twenty
Answer: 
This is the same as
and it is also equivalent to 
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Explanation:
n is some placeholder for a number
one fourth of that number is
which is the same as
or
since 1/4 = 0.25
From here, we subtract off 2 to get
as one possible final answer.
Answer: See explanation
Step-by-step explanation:
The perimeter of a pentagon is gotten through the summation of its five sides. Let the first side be represented by x. Since each side of a pentagon is 10 cm greater than the previous side, then the sides will be:
First side = x
Second side = x + 10
Third side = x + 10 + 10 = x + 20
Forth side = x + 30
Fifty side = x + 40
Therefore,
x + (x + 10) + (x + 20) + (x + 30) + (x + 40) = 500
5x + 100 = 500
5x = 500 - 100
5x = 400
x = 400/5
x = 80
Therefore, the lengths will be:
First side = x = 80cm
Second side = x + 10 = 80 + 10 = 90cm
Third side = x + 20 = 80 + 20 = 100cm
Forth side = x + 30 = 80 + 30 = 110cm
Fifty side = x + 40 = 80 + 40 = 120cm
Step-by-step explanation:
She made a sign error when multiplying and should have had 256 as a final answer.
<h2>
Answer with explanation:</h2>
Given : A standardized exam's scores are normally distributed.
Mean test score : 
Standard deviation : 
Let x be the random variable that represents the scores of students .
z-score : 
We know that generally , z-scores lower than -1.96 or higher than 1.96 are considered unusual .
For x= 1900

Since it lies between -1.96 and 1.96 , thus it is not unusual.
For x= 1240

Since it lies between -1.96 and 1.96 , thus it is not unusual.
For x= 2190

Since it is greater than 1.96 , thus it is unusual.
For x= 1240

Since it lies between -1.96 and 1.96 , thus it is not unusual.