Read the data given below and answer the questions based on it.
In the CBSE Board exams last year, 53% passed in Biology, 61% percent passed in English, 60% in Social studies, 24% in Biology and English, 35% in English and social studies, 27% in Biology and social studies and 5% in none.
What is the percentage of students who passed in all subjects?
In an election between two candidates, the winning candidate got 70% of the valid votes and won by a majority of 9000 votes. If out of total votes polled 90% votes are valid, then what is the total number of votes polled?
You went to buy 3 articles worth Rs.500 each. However, as per the discount sale going on in the shop, you paid for two and got one free. What is the discount percentage in the deal?