1) Given table shows how many plants Reena planted in a week.
| Days --> | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
| Number of plants | 20 | 20 | 22 | 18 | 18 | 27 | 30 |
a) Define average and formula to calculate average.
b)Find the average number of plants that Reena planted in the whole week.
2) The distance travelled by some students daily from the school is given below in kilometres
1 2 3 5 2 3 3 2 5 1 5 3 2
a) Draw frequency table with tally marks for given information.
b) Also find the average of the distance travelled by all the students on a day.
3) Is average an in useful in number? justify your answer.