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Help I need help with this

 

Sam writes down the numbers 1, 2, 3, ..., 99

 

(a) How many digits did Sam write, in total?

(b) Sam chooses one of the digits written down, at random. What is the probability that Sam chooses a 0?

(c) What is the sum of all the digits that Sam wrote down?

 Apr 19, 2023
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a. counting from 1 to 99 would take exactly 99 numbers

 

b. Do you mean the number 0, or a number containing 0?

 

c. take all the pairs of numbers that add up to 99 (aka 1 and 98, 2 and 97, 3 and 96 etc.) all the way to the end. the total should be around (49*99)+50

 Apr 19, 2023

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