To convert a number like 23a94b13 to base 10 in Mathematica, use the syntax base^^digits, where "base" is the numerical base and "digits" is the number in that base. For instance, to enter the hexadecimal number 1AD, you would write 16^^1AD. To display a number in a different base, utilize the BaseForm function, such as BaseForm[16^^1AD, 2] to print it in binary. Mathematica's help files are comprehensive and searchable, making them a valuable resource for users seeking assistance.