Multiple choice general knowledge

If x is the highest 4 digit number with base 4 and y is the least 5 digit number with base 5. What is y-x in decimal system?

  1. 34

  2. 45

  3. 100

  4. 99

  5. 370

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Highest 4-digit base-4 number = 3334₄ = 3·64 + 3·16 + 3·4 + 3 = 255₁₀. Least 5-digit base-5 number = 10000₅ = 625₁₀. Difference: 625 - 255 = 370 in decimal.