If the sum of the first 9 terms of an AP is equal to sum of the first 11 terms, then what is the sum of the first 20 terms ?

If the 5^th term of an AP is $\frac{1}{10}$ and its 10^th term is $\frac{1}{5},$ then what is the sum of first 50 terms ?

What is (1110011)₂ ÷ (10111)₂ equal to ?

If x³ + y³ = (100010111)₂ and x + y = (11111)₂, then what is (x - y)² + xy equal to ?