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:
107 comments Page 4 of 11.
Narendra said:
7 years ago
I don't understand about value of 14. In question they asking 1 or 9 but not 1&9. They asked about 1 or 9 so how could you consider as 14? Please explain clearly to understand.
Nicky said:
1 decade ago
In question he said 1 or 9 in the units digit there are 4 numbers between 1 to 10 whose unit digit ends between 1 and 9 they are 1, 3, 7, 9 so tell me that what is the solution?
Faraz said:
9 years ago
It is very simple.
Now there are 14 numbers which start from 1 or 9 It means 14 out of 70.
Now take percentage of 14 out of 70 means multiply by 100 which is equal to 20%.
Now there are 14 numbers which start from 1 or 9 It means 14 out of 70.
Now take percentage of 14 out of 70 means multiply by 100 which is equal to 20%.
Aditya Singh Shishodia said:
5 years ago
@All.
Unit place is the first digit and not the last. As per the place value system it would always begin from left to right. This is simply a wrongly phrased question.
Unit place is the first digit and not the last. As per the place value system it would always begin from left to right. This is simply a wrongly phrased question.
(2)
Durai said:
2 years ago
!All.
Here, They asked 1 or 9, why all answers are included both 1 and 9, if we considered 1 or 9 only the percentage should be 10%.
Correct me, if I'm wrong.
Here, They asked 1 or 9, why all answers are included both 1 and 9, if we considered 1 or 9 only the percentage should be 10%.
Correct me, if I'm wrong.
(15)
Tutu said:
10 months ago
How to know if we should take 1 or 70 to make 70 total numbers, like we could have written 13/68 to take a percentage?
Anyone, please explain.
Anyone, please explain.
(9)
Manikeshwari said:
2 years ago
@Moses Ug.
We can't consider 12 to 18 because the question says in units place of a number it should either have 1 or 9 not in tens place.
We can't consider 12 to 18 because the question says in units place of a number it should either have 1 or 9 not in tens place.
(2)
Anonymous said:
2 years ago
@All.
Here, In 1s digit there are 14 numbers with 1 and 9.
So 70% = 100.
14% = x.
Cross multiply.
70 (x) =14 (100).
X = 1400/70.
X = 20.
Here, In 1s digit there are 14 numbers with 1 and 9.
So 70% = 100.
14% = x.
Cross multiply.
70 (x) =14 (100).
X = 1400/70.
X = 20.
(8)
Cavendish said:
9 years ago
It has nothing to do with the squares.
Just count the numbers ending with 1 or 9 in between 1 and 70 (inclusively). That's all.
Just count the numbers ending with 1 or 9 in between 1 and 70 (inclusively). That's all.
Abhishek said:
8 years ago
@All.
If we increase the parameter from 70 to 100 then what?
I mean if we count from 1 to 100 than what will be the solution?
If we increase the parameter from 70 to 100 then what?
I mean if we count from 1 to 100 than what will be the solution?
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