SOLUTION: A two-digit random number is chosen. What is the probability that the sum of its digits is 5?

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Question 1120917: A two-digit random number is chosen. What is the probability that the sum of its digits is 5?
Found 2 solutions by ikleyn, Boreal:
Answer by ikleyn(52782) About Me  (Show Source):
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In all, there are 90 two-digit numbers from 10 to 99.


Of them, only these five numbers are favorable:  14, 23, 32, 41, 50.



Answer. Probability under the question is  5%2F90 = 1%2F18 = 0.0555. . . ~ 5.55%. 


Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
There are 90 possibilities (1-100) is 100, and subtract 1-9 and 100.
Sums are 1-4, 2-3,3-2,4-1,5-0. 5/90 or 1/18 is the probability.