Rajeshwar bought 16 dozen ball point pens and sold them by and by. Due

1.	Rajeshwar bought 16 dozen ball point pens and sold them by and by. Due to a calculation mistake in fixing selling price, he lost an amount equal to S.P. of 4 dozen pens. Find the loss per cent. Find the S.P. of one dozen pens, if he purchased these 16 dozen pens for Rs 240. (a) Rs 18 (b) Rs 10 (c) Rs 12 (d) Rs 14
Answer» (c) Rs 12 Let the S.P. of one dozen pens be Re x. Then, S.P of 16 dozen pens = Rs 16x Loss = S.P. of 4 dozen pens = Rs 4x \(\therefore\) C.P. = S.P. + Loss = Rs 16x + Rs 4x = Rs 20x \(\therefore\) Loss per cent =\(\big(\frac{4X}{20X}\times100\big)\) = 20% C.P. of 16 dozen pens = Rs 240, Loss = 20% \(\therefore\) S.P. of 16 dozen pens = Rs\(\frac{240\times80}{100}\) = Rs 192 \(\therefore\) S.P. of 1 dozen pens = Rs \(\frac{192}{16}\) =Rs 12

Rajeshwar bought 16 dozen ball point pens and sold them by and by. Due to a calculation mistake in fixing selling price, he lost an amount equal to S.P. of 4 dozen pens. Find the loss per cent. Find the S.P. of one dozen pens, if he purchased these 16 dozen pens for Rs 240. (a) Rs 18 (b) Rs 10 (c) Rs 12 (d) Rs 14

Answer»

(c) Rs 12

Let the S.P. of one dozen pens be Re x. Then,

S.P of 16 dozen pens = Rs 16x

Loss = S.P. of 4 dozen pens = Rs 4x

\(\therefore\) C.P. = S.P. + Loss = Rs 16x + Rs 4x = Rs 20x

\(\therefore\) Loss per cent =\(\big(\frac{4X}{20X}\times100\big)\) = 20%

C.P. of 16 dozen pens = Rs 240, Loss = 20%

\(\therefore\) S.P. of 16 dozen pens = Rs\(\frac{240\times80}{100}\) = Rs 192

\(\therefore\) S.P. of 1 dozen pens = Rs \(\frac{192}{16}\) =Rs 12