by selling 20 pencils for a rupee a man loses 60 %. how many for a rupee should he sell in order to gain 60 %?  Choose one.
A) 8	B) 9	C) 7	D) 6	E) 5
<gadget id="calculator">100 + 60</gadget>
<output>160</output>

<gadget id="calculator">100 - 60</gadget>
<output>40</output>

<gadget id="calculator">1 / 40</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">160 * (1/40)</gadget>
<output>4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/4) * 20</gadget>
<output>5</output>

<result>E</result>
by selling 20 pencils for a rupee a man loses 60 %. how many for a rupee should he sell in order to gain 60 %?
multiply(divide(const_1, multiply(add(const_100, 60), divide(const_1, subtract(const_100, 60)))), 20)
"40 % - - - 20 160 % - - - ? 40 / 160 * 20 = 5 answer : e"