Question

I bought 5 pens, 7 pencils and 4 erasers. Rajan bought 6 pens, 8 erasers and 14 pencils for an amount which was half more what I had paid. What percent of the total amount paid by me was paid for the pens?

• A. 37.5 %
• B. 62.5 %
• C. 50 %
• D. None of these

Answer 1

The correct option is B 62.5 %

Let one pen, one pencil and one eraser cost = n, p, r units
Let the amount paid by me = A
$\therefore IPay=(5n+7p+4r)=A..1$
While Rajan pay $(6n+14p+8r)=1.5A..2$
Now multiply 1 by 2
we get
$\Rightarrow (10n+14p+8r)=2A...3$
Comparing 2 and 3 We see that while Rajan gets 4pen less ,he pays 0.5A unit less.
Thus A = the price of 8 pen
$\therefore thepercentofthetotalpricepaidbymeinitiallywhichwasusedforpens=\frac{5}{8}\times 100=62.5$