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.
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%.
