What is the "range" of a set of data?

When is it more convenient to use a grouped frequency distribution instead of a simple frequency distribution?

For the class interval 31-40, what are the upper and lower class limits, and what is the mid-value?

What is the "modal class" in a grouped frequency distribution?

Explain the difference between discrete and continuous data, and give one example of each.

Write the formula for calculating the mean of a grouped frequency distribution using mid-values.

A frequency distribution of marks received by 30 students is given. The class interval 21-30 has a frequency of 13. If the mid-value is 25.5, what is the value of fx for this class interval?

What is the purpose of using an "assumed mean" when calculating the mean of a grouped frequency distribution?

Write the formula for calculating the mean using an assumed mean.

In a distribution, the assumed mean (A) is the mid-value of the modal class, 39. The sum of the frequencies (∑f) is 50, and the sum of the products of frequency and deviation (∑fd) is -120. Calculate the actual mean.

A survey on the ages of 100 TV viewers is conducted. 31 viewers are in the 35-45 age group. If you take the mid-value of this class as the assumed mean, what is the deviation (d) for the 15-25 age group?

The mean number of shirts produced per day in a factory is 40. How many shirts can be expected to be produced in a month with 25 working days?

In a frequency distribution of teachers' ages, the class interval 31-36 has a frequency of 51. The total number of teachers is 185. What percentage of teachers belong to the modal class?

A distribution of marks obtained by 240 students is given. If the top 20% are to be awarded distinctions, how many students will receive this award?

In a survey of 100 households, the mean number of electricity units used was 65. The Electricity Board charges Rs 14 per unit for usage between 61-90 units. Estimate the income the Board can expect from these 100 households.