How many natural numbers less than a lakh can be formed with the digits 0,6 and 9?
A. 242
B. 243
C. 728
D. 729
Answer: Option A
Solution(By Examveda Team)
The digits to be used are 0,6 and 9 The required numbers are from 1 to 99999 The numbers are five digit numbers. Therefore, every place can be filled by 0, 6 and 9 in 3 ways. Total number of ways = 3 × 3 × 3 × 3 × 3 = 35 But 00000 is also a number formed and has to be excluded. Total number of numbers, = 35 - 1= 243 - 1
= 242
This Question Belongs to Arithmetic Ability >> Permutation And Combination
In the Question, given Natural numbers and Natural Number is define as
Natural Numbers:
The numbers which are used for counting {such as 1,2,3,4,5,6,7..........so on.} are known as Natural numbers. The positive integers are also known as natural numbers.
Thus 4567 is a natural number but 0, -3, 14.6, 3/4 etc. are not natural numbers.
0 is not a natural number so it is not there.
one doubt y r we taking numbers from 1 to 99999 rather than 0 to 99999