Binary, Octal, and Hexadecimal Conversions

Use positional notation to convert from Base$-$X to Base$-10.$

Examples

$1010$ Base$-2$ to Base$-10$:

Convert a binary $($base$-2)$ number $1010110$ to decimal.

$754$ in octal $($base $8)$ to decimal

Hexadecimal number ABC to decimal

$642$ Base$-13$ to Base$-10$: