Question

sol. (4) Required S.P. of 150 pens. ( =150 times 12 times frac{115}{100}=₹ 2070 )
S.P. of first 50 pens
( =frac{50 times 12 times 110}{100}=₹ 660 )
( therefore ) Required S.P. of 100 pens ( =2070-660=₹ 1410 )
C.P. of 100 pens ( =₹ 1200 )
( therefore ) Gain per cent ( =frac{210}{1200} times 100 )
( =frac{35}{2}=17 frac{1}{2} % )

# Ex.2. A man purchased 150 pens at the rate of 12 per pen. He sold 50 pens at a gain of 10%. The percentage gain at which he must sell the re- maining pens so as to gain 15% on the whole outlay is (1) 21% (2) 20% (3) 17% (4) 17+%

Solution