What class boundaries to use when the class intervals is 0.0-0.9,1.0-1.9...so on..?

Question

what we take to draw the histogram when x is 5,8,9,12..etc.?

Answer 1

From the class intervals it appears that the data were measured to the nearest 0.1, for example they could be weights to the nearest 0.1kg.  If so, the data are continuous.  A value such as 0.94 is rounded to 0.9.  In fact any value greater than 0.9 and less than 0.95 is rounded down to 0.9.  A value equal to or greater than 0.95 and less than 1.0 is rounded up to 1.0.

Therefore the boundary between 0.9 and 1.0 is 0.95.  The next boundary is 1.95 and so on.

There is a problem with the first class's lower boundary.  I am assuming that the lowest possible value is 0 and that it would not be possible to have a reading equal to -0.05 that has been rounded up to 0.  Therefore the lower boundary of the first class is 0 and not -0.05.

Answer 2

Just pick half-way between the intervals: -0.05, 0.95, 1.95, 2.95, etc.