Radha is drawing a dot Rangoli (a beautiful pattern of lines joining dots) with chalk powder. She has 9 dots in a row. How many dots will her Rangoli have for r rows? How many dots are there if there are 8 rows? If there are 10 rows?

Change the following statements using expressions into statements in ordinary language. (For example, Given Salim scores r runs in a cricket match, Nalin scores (r +15) runs. In ordinary language-Nalin scores 15 runs more than Salim.)(e) In an arrangement of dots there are r rows. Each row contains 5 dots.

There are 10 candidates for an examination out of which 4 are appearing in Mathematics and remaining 6 are appearing indifferent subjects. In how many ways can they be seated in a row so that no two Mathematics candidates are together?

A family consists of a grandfather, 5 sons and daughters and 8 grand child. They are to be seated in a row for dinner. The grand children wish to occupy the 4 seats at each end and the grandfather refuses to have a grandchild on either side of him. In how many ways can the family be made to sit?

Had Ajita scored 10 more marks in her mathematics test out of 30 marks, 9 times that number would have been the square of her actual marks. How many marks did she get in the test?

There are 500 children in a school.For a P.T. drill they have to stand a manner that the number of rows is equal to number of columns.How many children would be left out in this arrangement?