Question

Write each of the following numerals in base 10. For base twelve, T and E represent the face values ten and eleven, respectively.

a. 421 five
b. 11101 two
c. 13Ttwelve

Answer 1

(a)

421₅ = 4×5² + 2×5¹ + 1×5⁰

… = 100 + 10 + 1

… = 111

(b)

11101₂ = 1×2⁴ + 1×2³ + 1×2² + 0×2¹ + 1×2⁰

… = 16 + 8 + 4 + 0 + 1

… = 29

(c)

13T₁₂ = 1×12² + 3×12¹ + 10×12⁰

… = 144 + 36 + 10

… = 190