IQR = 6
First locate the median 
at the centre of the data arranged in ascending order. Then locate the lower and upper quartiles 
and 
located at the centre of the data to the left and right of the median.
Note that if any of the above are not whole values then they are the average of the values either side of the centre.
rearrange data in ascending order
15 16 ↓17 17 18 21 22 ↓23 25
↑
= 18
= 
= 16.5
= 
= 22.5
IQR = - = 22.5 - 16.5 = 6
When x is -1 Y will equal -1
Answer:
The weight can vary from 22.5 to 25.5
(X1=1, y1=7) and (x2= -4, y2 =-8)
Slope = ( y2-y1)/(x2-x1)= (-8-7)/(-4-1)= -15/-5=3
Slope is 3
Okay. First thngs first, let's divide each of them. 2.6/1.3 is 2. Now in terms of exponents, we would just simply subtract the powers, because we are doing division. 9 - 2 is 7. The value of the expression is 2 * 10^7. Even writing the problem out in number form (2,600,000,000/130), you can still see the answer to the problem as 20 million. The answer is B.
