In a hostel of 50 girls, there are food provision for 40 days.If 30 more girls join the hostel,how long will these provisions last ?

There are 100 students in a hostel. Food provision for them is for 20 days. How long will these provisions last, if 25 more students join the group?

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : A part of monthly hostel charges in a college are fixed and remaining depend on number of days one has taken food in the mess. When a student A takes food for 20 days, he has to pay rs 1000 as hostel charges whereas student B who takes food for 26 days has to pay rs 1180 as hostel charges. Find fixed charges and cost of food per day.

The teperature dropped 15 degree celsius in the last 30 days.If the rate of temperatue drop remains the same,how many degrees will the temperature drop in the next ten days?

A farmer has enough food to feed 20 animals in his cattle for 6 days. How long would the food last if there were 10 more animals in his cattle?

In a college hostel acomodating 1000 students, one of them came in carrying a flue virus, then the hostel was isolated. If the rate at which the virus spreads is assumed to be proportional to the produce of number of infected students and the number of non-infected students and if the number of infected students is 50 after 4 days then show that more than 95% of the students will be infected after 10 days

From a class of 12 boys and 10 girls, 10 students are to be chosen for a competition, at least including 4 boys and 4 girls. The 2 girls who won the prizes last year should be included. In how many ways can the selection be made ?

Observe the histogram and answer the questions given below : If we divide the girls into the following three categories,how many would there be in each ? 150 cm and more in Group A 140 cm to less in Group C.

Observe the histogram (Fig.) and answer the questions given below : If we divide the girls into the following three categories, how many would there be in each ? {:("150 cm and more - Group A"),("140 cm to less than 150 cm - Group B"),("Less than 140 cm - Group C"):}