Summing up Odd Numbers from One

Q. The sum of two consecutive triangular numbers is a square number.

1. False
2. True

Q. Find the sum of 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 +19, without performing each term addition.

1. 100
2. 64
3. 90
4. 81

Q.

The sum of first 16 odd numbers is ___.

1. 286

2. 296

3. 246

4. 256