What percentage of numbers from 1 to 70 have 1 or 9 in the unit's digit?  Choose the most appropriate option
A) 20(2/3)%  B) 20%  C) 21%  D) 22(2/3)%  E) None of these
Explanation :   Total numbers = 70   Total numbers in 1 to 70 which has 1 in the unit digit = 7   Total numbers in 1 to 70 which has 9 in the unit digit = 7   Total numbers in 1 to 70 which has 1 or 9 in the unit digit = 7 + 7= 
<gadget id="calculator">7 + 7</gadget>
<output>14</output>
14   Required percentage= (14/70) × 100 = 140/7= 
<gadget id="calculator">140/7</gadget>
<output>20</output>
20%   Answer : Option 20%
<result>B</result>
What percentage of numbers from 1 to 70 have 1 or 9 in the unit's digit?