Question

If the rate of notebooks is ₹ 240 per dozen, what is the cost of 3 notebooks? Also find the cost of 9 notebooks ; 24 notebooks and 50 notebooks and complete the following table.
Number of notebooks (x) 12 3 9 24 50 1
Cost (In Rupees) (y) 240 20 ... ... ... ...

Answer 1

Dear student,

Solution:

Rate of notebooks per dozen = 240 Rs.

We know that number of notebook in one dozen is 12.

To solve the question ,first calculate the cost of one notebook .

if 12 notebook has purchased in 240 rupees

then 1 notebook is purchased in= 240/12

= 20 Rupees

Now cost of 3 notebooks = 3 X 20

= 60 Rupees

Now cost of 9 notebooks = 9 X 20

= 180 Rupees

Now cost of 24 notebooks = 24 X 20

= 480 Rupees

Now cost of 50 notebooks = 50 X 20

= 1000 Rupees

Find Table in attachment.

first column shows number of notebooks,second column shows amount in rupees.

hope it helps you.

Answer 2

According to the question the rate of notebooks is rupees 240 for 12 notebooks.

Therefore the rate of one notebook will be Rs (240 / 12) = Rs 20.

Therefore cost of 3 notebooks is 3 times rupees 20 i.e. Rs 60.

Similarly cost of 9 notebooks 24 notebooks and 50 note books are:

9 x 20 = Rs 180

24 x 20 = Rs 480

50 x 20 = Rs 1000