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3 years ago

15

Jonah's favourite number is a positive integer. One day, he decided to write down all of the positive integers starting at 1 and

ending with his favourite number. He noticed, in doing so, that he wrote the digit 7 exactly 30 times. What is Jonah's favourite number?

1 answer:

masya89 [10]3 years ago

3 0

Answer:

um I think its 14

Step-by-step explanation:

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