I wanted to know what are the books for Number theory i am preparing for RMO and also i have not been intoduced to number theory in my previous classes can you tell me a books name that has enough theory to understand and a problem solving approach.

What are the differences between similar triangles and congruent triangles?

What are Armstrong numbers?

All real numbers are rational numbers.

A) True

B) False

The L.C.M of the smallest 2 digit composite number and the smallest composite number is:

• (a) 12
• (b) 4
• (c) 20
• (d) 44

Are all natural numbers also whole numbers?