Question

The cost of one pen is rupees 7 then what is the rule for the cost of n pens​

Answer 1

● If the cost of a pen is 7 rupees then the cost of N pens will be 7n.

● We can get this by applying the rule for the cost.

● According to rule for the cost, the cost of single item should be multiplied with the the number of items that are to be sold to get the total amount that is cost price of that many items.

● Hence cost of single pen is 7 and it should be multiplied with n number of pens as n number of pens are sold.

● So the cost price of n number of pens is 7n.

Answer 2

Given:

1. The cost of one pen = Rs. 7

To find:

1. Cost of n pens

Solution:

To solve this question, we will apply the unitary method as follows:

It is given to us that,

1. Cost of 1 pen = Rs. 7
2. Let the cost of n pens = Rs. x

Then, applying the unitary method,

The cost of n pens will be x =  7 × n = Rs. 7n

Thus, the cost of n pens will be Rs. 7n.