Aptitude - Percentage - Discussion
Discussion Forum : Percentage - General Questions (Q.No. 4)
4.
What percentage of numbers from 1 to 70 have 1 or 9 in the unit's digit?
Answer: Option
Explanation:
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
 Required percentage = |
 |
14 | x 100 |  % = 20%. |
| 70 |
Video Explanation: https://youtu.be/cBamI6iRNIA
Discussion:
102 comments Page 9 of 11.
Muskan said:
6 years ago
I am not understanding, please anyone explain me.
Mustafa said:
8 years ago
Why 12, 13, 14, 15, 16, 17, 18 are not included?
Abba said:
8 years ago
What about 11, 12, 13, 14, 15, 16, 17, and 18?
Gnanikrishna said:
5 years ago
What is the unit's digit? Please explain me.
(2)
Aditys said:
8 years ago
The question should be 1 and 9 not 1 or 9.
Arushi said:
5 years ago
@Jim.
The unit digit is the ending digit.
The unit digit is the ending digit.
Aadya said:
10 years ago
7x7= 49.
4(9) why don't we count 7 then?
4(9) why don't we count 7 then?
Rasheed nasar said:
3 years ago
Very helpful explanation, Thanks. @Tabi.
(3)
Honey said:
9 years ago
Thanks for your clear solution @Tabi.
Diwaker said:
1 decade ago
What about 12 13 14, 15, 16, 17, 18?
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