In the class intervals given as 0-10, 10-20, ..... and so on, the number 22 is included in the class interval :
30-20
10-20
20-30
more than 25
Choose the correct answer in each of the following questions: In the class intervals 10-20, 20-30, the number 20 is included in (a) 10-20 (b) 20-30 (c) in each of 10-20 and 20-30 (d) in none of 10-20 and 20-30