(i) Can a rectangular number be a square number?

(ii) Can a triangular number be a square number?

Observe the following pattern and fill in the blanks:

1 × 9 + 1 = 10

12 × 9 + 2 = 110

123 × 9 + 3 = 1110

1234 × 9 + 4 = …….

12345 × 9 + 5 = …….

Look at the following figures made up of dots:

These figures show the arrangement of the numbers 2 × 3 or 3 × 2; 2 × 4 or 4 × 2 i.e. the numbers 6 and 8.

The numbers 6 and 8 are called rectangular numbers. Can you write two more rectangular numbers?

Fill in the blanks:

(i) A whole number is less than all those whole numbers that lie to its …. on the number line.

(ii) One more than a given whole is called its ….

(iii) There is at least one whole number between two …. whole numbers.

(iv) 738 × 335 = 738 × (300 + 30 + ….)

(v) If a is a non-zero whole number and a × a = a, then a = ….

(vi) …. is the only whole number which is not a natural number.

(vii) The additive identity in whole numbers is ….

(viii) …. is the successor of the largest 3-digit number.

(ix) Division of a whole number by …. is not defined.