What is $62_7+34_5$ when expressed in base 10?
To convert a number from another base to base 10, I need to multiply each digit by the base raised to the power of its position, starting from the rightmost digit as the zeroth power. For example, $62_7$ means $6\cdot 7^1+2\cdot 7^0=42+2=44$ in base 10. Similarly, $34_5$ means $3\cdot 5^1+4\cdot 5^0=15+4=19$ in base 10. Now I just need to add these two numbers in base 10: $44+19=63$. 