A man spends (1/7)th of his salary on food, half of the remaining on clothing and (1/3)rd of the remaining on entertainment. He is still left with Rs. 600. How much does he spend on entertainment?

Here, we have two sections A and B. Section A has 3 question and B has 5 question and one question from each section is compulsory according to the given condition.
? Number of ways selecting one or more than one question from section A
= 2³ - 1 = 7
Similarly, from section B = 2⁵ - 1 = 31
According to the rule of multiplication, the required number of ways in which a candidate can select the question
= 7 x 31 = 217

4th observation i.e., 8 is the median.

47/10000 = .0047

.02 =(2/100) x 100% =2%

Let N / 11 = 233
Then, N = 233 x 11 = 2563
? Missing digit is 5.

121012 = 12 x 10084 + 4
? remainder = 4

We have the important relation, More work, More time (days)
? A piece of work can be done in 6 days.
? Three times of work of same type can be done in 6 x 3
= 18 days