What do you know about range?

Count on in intervals by looking at the highest value in the data.

Recall the class mark formula and follow with corrosponding class marks.

What do you know about range?

Mid value of the class - (class width)/2

What is the formula to calculate class mark of any class interval?

Think about the numbers which can be grouped in the class 105-110.

By putting the values given in all the options, you can find the class mark and width of class.

Remember, we can not use the same mark more than 4 times.

Width of class is the difference between the upper or lower limits of consecutive classes.