E$1$F$9$ from base$-16$ to base$-2$

$1111010111110100$ from base $-2$ to base$-10$

$7101$ from base$-8$ to base$-16$

$15678$ from base $-10$ to base $-16$

FF$9$A from base$-16$ to base$-2$

$101111111011$ from base$-2$ to base$-8$

F$7$D$9$ from base$-16$ to base$-8$

$123478$ from base$-10$ to base$-16$

$70101$ from base$-8$ to base$-10$

$457$ from base$-8$ to base $16$