Question

A man bought some pens for ₹60. If the price of each pen had been ₹1 less, he would have got 3 pens more, how much did each pen cost him (in ₹)​

Answer 1

Answer:

A boy bought some pencils for $60. If he had paid $1 less for each pencil, he could have bought 5 more pencils. How many pencils did he pay for?

Answer =15

Now calculation starts as,

As per the information given , if we decrease the cost per pencil by 1 then we can get more of 5 pencils, so

Taking a simple approach

We get a hint that it might be a number nearing 5, that is a cost for one pencil, so

60/5=12

And reducing amount per pencil by one,

60/4=15

Similarly ,

60/3=20

i.e, +5 than the previous number of pencils bought.

And volla, we have the answer is 15.

Answer 2

Answer:

The cost of each pen is 5₹.

Step-by-step explanation:

Let each pen cost x₹

Now as per question,

if he had paid 1₹ less for each pencil he would have got 3 pens more.

so, $\frac{60}{x-1} -\frac{60}{x} =3$

Take L.C.M(x, x-1)

$\frac{60x-60(x-1)}{x(x-1)} =3\\60x-60x+60=3x(x-1)\\60=3x^{2} -3x\\3x^{2} -3x-60=0\\x^{2} -x-20=0$

now factorize $x^{2} -x-20=0$

⇒

$x^{2} -5x+4x-20=0\\x(x-5)+4(x-5)=0\\(x+4)(x-5)=0$

$x=5$ as $x$ cannot be negative.

This 5₹ is the cost of each pen and for 60₹ initially 60÷5 = 12 pens could have been got.