4. Some Properties of Square Numbers The unit digit of a number
ending in 0 is always 0. The unit digit of a number ending in 1 or
9 is always 1. The unit digit of a number ending in 2 or 8 is
always 4. The unit digit of a number ending in 5 is always 5. The
unit digit of a number ending in 4 or 6 is always 6. The unit digit
of a number ending in 3 or 7 is always 9. So, the unit digit of a
square number is always 0,1,4,5,6,9.
5. Examples Number Square 10 100 20 400 Number Square 9 81 11
121 Number Square 12 144 18 324 Number Square 14 196 16 256 Number
Square 5 25 15 225 Number Square 13 169 17 289
6. Practice Questions Q1. Square of which of the following
numbers will have 1 in its unit place? 29, 25, 18, 31, 49, 52, 21,
55 Q2. Square of which of the following numbers will have 6 in its
unit place? 24, 85, 13, 76, 54, 41, 58, 66 Q3. Square of which of
the following numbers will have 9 in its unit place? 36, 23, 77,
84, 47, 53, 67, 22