Answer:
The even numbers between 0 and X represents an arithmetic sequence with a common difference of 2
The rule of arithmetic sequence = a + d(n - 1)
Where a is the first term and n is the number of terms
So, for the even numbers between 0 and X
The first term = a = 0
d = 2
So, we need to find n at the last term which is X
∴ X = 0 + 2 ( n -1 )
∴ n - 1 = X/2
∴ n = X/2 + 1
The sum of the arithmetic sequence = (n/2) × (2a + (n−1)d)
Substitute with a and d and X
So, the sum = (n/2) * (2*0 + (n−1)*2)
= (n/2) * ((n−1)*2)
= n(n-1)
= (X/2 + 1) * (X/2)
= X/2 by (X/2 + 1)
So, The quick way to add all even numbers between 0 and X always works.
<em>3,2</em>
Step-by-step explanation:
Reflection across the x-axis:
(x,y) -> (x,-y)
In other words, you want to <u>change the sign of the y</u>.
(3,-2) -> (3,2)
To find the range you subtract the largest number from the smallest 20-13=7. To find the interquartile range you have to find the median of the data set. The median is 18.5, now there are two sets split in half. The median for the lower quartile is 14.5 and the median for the upper quartile is 19. Range=7 and IQR=18.5-14.5=4. IQR=4
