A natural numberis chosen at randomfromthe first hundred numbers. The probability that the numberis divisible by 3 or 5 is

Total multiples of 3 in the first 100 natural numbers: 33..... (A)
Total multiples of 5 in the first 100 natural numbers: 20..... (B)

The total numbers upto 100 which are divisible by either 3 or 5 = A + B - Common numbers in set A and B
The common numbers will be 15, 30, 45, 60, 75, 90 i.e. total of 6 such numbers.

Hence, the desired answer = 53-6 = 47
Hence, the probability of selecting a number from 1 to 100 which is divisible by either 3 or 5 = 47/100