An automobile owner reduced his monthly petrol consumption when the prices went up. The price-consumption relationship is as follows:

Price (in Rs. per litre) 40 50 60 75 Monthly consumption (in litres) 60 48 40 32

If the price goes up to Rs. 80 per litre, his expected consumption (in litres) will be

A student has to opt for 2 subjects out of 5 subjects for a course, namely, Commerce, Economics, Statistics, Mathematics I, and Mathematics II. Mathematics II can be offered only if Mathematics I is also opted. The number of different combinations of two subjects that can be opted is:

In a box of marbles, there are 3 fewer white marbles than red ones and 5 more white marbles than green ones. If there are 10 white marbles, how many marbles are in the box?

In a parking area, the total number of wheels of all the cars (four-wheelers) and scooters/motorbikes (two-wheelers) is 100 more than twice the number of parked vehicles. The number of cars parked is:

The monthly incomes of Peter and Paul are in the ratio of $4:3$. Their expenses are in the ratio of $3:2$. If both save Rs. 6000 at the end of the month, their respective monthly incomes are:

There are 5 tasks and 5 persons. Task-1 cannot be assigned to person-1 or person-2. Task-2 must be assigned to person-3 or person-4. Each person is to be assigned one task. In how many ways can the assignment be done?