Question

Convert the binary number 10101 to its base 10 equivalent.

12
21
22
31

Answer 1

Here see below

`\\ \sf\Rrightarrow (10101)_2`

`\\ \sf\Rrightarrow 1* 2^0+0* 2^1+1* 2^2+0* 2^3+1* 2^4`

`\\ \sf\Rrightarrow 1+4+16`

`\\ \sf\Rrightarrow (21)_(10)`

Answer 2

10101₂ = 1×2⁴ + 0×2³ + 1×2² + 0×2¹ + 1×2⁰

10101₂ = 16 + 0 + 4 + 0 + 1

10101₂ = 21