If you randomly drew a number between 1 and 100,000, what is the probability that its digits sum up to 22? Thanks for any help.

Guest Aug 4, 2020

#1**0 **

I don't know how to solve it mathematically, but I can write a short computer code to find out how many numbers are there between 1 and 100,000 whose digits sum up to 22. Here is the code:

%%time;# Function to return the sum of digits of x between L and R #

def sumOfDigits(x):

sum = 0

while x != 0:

sum += x % 10

x = x//10

return sum

# Function to return the count

# of required numbers

def countNumbers(L, R):

count = 0

for i in range(L, R + 1):

# ENTER SUM OF DIGITS HERE #

if sumOfDigits(i)==22:

count += 1

return count

L =1; R = 99999

print("Total = ", f"{countNumbers(L, R):,d}")

**OUTPUT =6,000 [Exactly!]. Therefore, the probability is: 6,000 / 100,000 ==6%.**

Guest Aug 4, 2020