Answer:
Therefore the answer is 20.
Step-by-step explanation:
We know that
class interval = range / number of classes
But here number of classes is not given , so we use the formula
class interval = range / ( 1+ 3.322 log N)
where , range =maximum - minimum = 220-100 = 120
N= number of observations = 50
class interval = 120 / ( 1+ 3.322 * log 50) = 18.06
Rounding up to a convinient number
Thus , class intervai = 20
Therefore the answer is 20.
