Browse · MATH Print → jmc number theory intermediate Problem In a certain base b, the square of 22b is 514b. What is b? Solution — click to reveal We have that 22b=2b+2 and 514b=5b2+b+4. Hence, (2b+2)2=5b2+b+4, which simplifies to b2−7b=0. This equation factors as b(b−7)=0, so b=7. Final answer 7 ← Previous problem Next problem →