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 10 of 11.
Arjun said:
9 years ago
Please explain, what is unit digit?
Saranya said:
1 decade ago
Thank you for your short cut syed.
Sreekanth said:
1 decade ago
Why don't you take 12, 13, 14...?
Niraj said:
1 decade ago
What about 12,13,14,15,16,17,18?
Kamall Barik said:
8 years ago
Thanks for your shortcut @Syed.
Naga said:
1 decade ago
I con't understad this problem
Rishav said:
9 years ago
Why you put 11 21 31and all?
Kiran shahzadi said:
1 decade ago
What is mean by unit digit?
Karthik said:
2 decades ago
Any short cut for this?
Subash said:
7 years ago
Thank you @Manisha.
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