The cost of 6 pens and 19 pencils is ₹275. If the cost of a pen decreases by ₹7 and the cost of a pencil increases by ₹7, then the cost of 15 pens and 4 pencils is ₹132. What is the original cost of 6 pens and 2 pencils?

Let cost of one pen = ₹$x$ and one pencil = ₹$y$

Given:
$6x + 19y = 275$

After changes:
Pen = $(x - 7)$, Pencil = $(y + 7)$

$15(x - 7) + 4(y + 7) = 132$

$15x - 105 + 4y + 28 = 132$

$15x + 4y - 77 = 132$

$15x + 4y = 209$

Now solve:
$6x + 19y = 275$
$15x + 4y = 209$

Multiply first equation by 5:
$30x + 95y = 1375$

Multiply second by 2:
$30x + 8y = 418$

Subtract:
$87y = 957 \Rightarrow y = 11$

Put in first:
$6x + 19(11) = 275$
$6x + 209 = 275$
$6x = 66 \Rightarrow x = 11$

Now required:
$6x + 2y = 6(11) + 2(11) = 66 + 22 = 88$

Correct Answer: ₹88