A number is increased by 70 % and then decreased by 70 %. Find the net increase or decrease per cent.
Choices:
A) 49%
B) 18%
C) 17%
D) 13%
E) 16%
Let the number be 100.   Increase in the number = 70 % = 70 % of 100   = (70/100 Ã— 100)   = 70   Therefore, increased number = 100 + 70= 
<gadget id="calculator">100 + 70</gadget>
<output>170</output>
170   This number is decreased by 70 %   Therefore, decrease in number= 70 % of 170   = (70/100 Ã— 170)   = 11900/100= 
<gadget id="calculator">11900/100</gadget>
<output>119</output>
119   Therefore, new number= 170 - 119= 
<gadget id="calculator">170 - 119</gadget>
<output>51</output>
51   Thus, net decreases= 100 - 51= 
<gadget id="calculator">100 - 51</gadget>
<output>49</output>
49   Hence, net percentage decrease= (49/100 Ã— 100) %   = (4900/100)= 
<gadget id="calculator">(4900/100)</gadget>
<output>49</output>
49 %   49%nswer:49%
<result>A</result>
A number is increased by 70 % and then decreased by 70 %. Find the net increase or decrease per cent.