What percentage of numbers from 1 to 70 have 1 or 9 in the unit's digit?
  • 11
  • 214
  • 320
  • 421
Answer:- 1
Explanation:-

Solution:
Clearly, the numbers which have 1 or 9 in the unit's digit, have squares that end in the digit 1. Such numbers from 1 to 70 are 1, 9, 11, 19, 21, 29, 31, 39, 41, 49, 51, 59, 61, 69.
Number of such number =14
=(1470×100)%=20%.

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "
Solution:
Clearly, the numbers which have 1 or 9 in the unit's digit, have squares that end in the digit 1. Such numbers from 1 to 70 are 1, 9, 11, 19, 21, 29, 31, 39, 41, 49, 51, 59, 61, 69.
Number of such number =14
=(1470×100)%=20%.
", "dateCreated": "7/24/2019 10:09:12 AM" } }
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