Question

The cost of 5 pens is ₹60 and cost of one book is ₹83. What will be the total cost of 15 pens and 2 books?

• A. ₹94
• B. ₹126
• C. ₹346
• D. ₹462

Answer 1

The correct option is C ₹346

The cost of 5 pens = ₹60
15 pens would cost = ₹60 × 3
We can multiply 6 and 3 first then add a zero at the end.
We know that 6x3 = 18
Now we can add zero at the end so that will make it ₹180

So, the cost of 15 pens = ₹180

Now to find the cost of two books we need to multiply
₹83 x 2
This can also be calculated as follows:
$$\begin{array}{ccc}\times & 80& 3\\ 2& 2\times 80=160& 2\times 3=6\end{array}$$
We get the desired result by adding the numbers in last row
= 180 + 166 = 720
Hence, the total cost = ₹346