कोशिका: सरंचना एवं प्रकार्य | CLASS 8 विज्ञान | 5 PM Class by Nishtha Ma'am | L1 | Hindi Medium

12 PM Special Class | Class 11 - STRUCTURE OF ATOM || BOHR MODEL By Yakshu Ma'am

The probability that a student selected at random from a class will pass in Hindi is 4/5 and the probability that he passes in Hindi and English is 1/2 . What is the probability that he will pass in English if it is known that he has passed in Hindi ?

In a class of 50 students, 23 speak English, 15 speak Hindi and 18 speak Punjabi. 3 speak only English and Hindi, 6 speak only Hindi and Punjabi and 6 speak only English and Punjabi. If 9 speak only English, then how many speak all the three? (a) 1 (b) 2 (c) 3 (d) 5

Thirty children were asked about the number of hours they watched TV programmes in the previous week. The results were found as follows: 1 6 2 3 5 12 5 8 4 8 10 3 4 12 2 8 15 1 17 6 3 2 8 5 9 6 8 7 14 12 (i) Make a grouped frequency distribution table for this data, taking class width 5 and one of the class intervals as 5 - 10. (ii) How many children watched television for 15 or more hours a week?

The dimensions of a class room are 10m, 8m, and 5m. Find the cost of decorating its walls by a wall paper of 1 m width, which costs rs. 50 per metre.

In a frequency distribution table with 12 classes, the class-width is 2.5 and the lowest class boundary is 8.1, then what is the upper class boundary of the highest class?

The average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of the girls is 15.4 years. The ratio of the number of boys to the number of girls in the class is (a) 1 : 2 (b) 2 : 3 (c) 3 : 4 (d) 3 : 5