If 4 whole numbers are taken at random and multiplied together. What is the probability that last digit in the number is 1,3,7,9? Please give the explanatjon steps.

Dear student,

Required probabilty is 1/4.

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Askiitians Expert

Sagar Singh

B.Tech, IIT Delhi

Approved

I think what you are saying may be wrong. I reason out as follows:

See since we are multiplying 4 whole numbers, the numbers of ways in which any of the numbers (0, 1...9) can come in the end(units place) is 4. So according to me the total number of ways should be 10⁴.

And hence 1,3,7,9 can come in units place in 4⁴ ways so the answer should be:

4^4/10⁴ = (2/5)⁴

Please correct me if i''m wrong and plz tell me why.