Class-7,8

The bar graph below shows the percentage break-up of the number of student who visited various touris spots on new Year evening. The table shows the total numbers of students om classes X,XI and XII . {:("Class","No. of students"),(X,420),(XI,480),(XII,400):} If the ratio of girls and boys, who went to Manali from class X, was 7:8 , then what percent of the total number of students from class X who went to a turist spot is the number of girls who went to Manali ? (approximate)

If a class mark of a class-interval 8.5. The class size is 5,then the class limits of the corresponding class-interval is

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?

Find the mean of the following frequency distributions: Class interval: 0-8 8-16 16-24 24-32 32-40 Frequency: 6 7 10 8 9