In a stack there are 6 magazines, each of having thickness 20mm and 5 sheets of paper each of thickness 0.016mm. What is the total thickness of the stack (in mm)?

Hint – In this particular type of question use the concept that the thickness of the stack is equal to the sum of the thickness of the 6 magazines and the thickness of the 5 sheet of paper so use this concept to reach the solution of the question.

Complete step by step solution:
Given data:
There are 6 magazines
Thickness of each magazines = 20mm
And there are 5 sheet of paper
Thickness of each sheet of paper = 0.016mm.
So, 6 magazines and 5 sheets of paper together makes a stack.
Now we have to calculate the thickness of the stack.
So the thickness of 6 magazines is equal to the product of thickness of one magazine and the number of magazines.
So the thickness of the 6 magazines = 6(20) = 120mm
Now the thickness of 5 sheets of paper is equal to the product of the thickness of one sheet of paper and the number of sheets of paper.
So the thickness of the 5 sheets of paper = 5(0.016) = 0.080mm.
So the thickness of the stack is equal to the sum of the thickness of the 6 magazines and the thickness of the 5 sheet of paper.
So the thickness of the stack = thickness of the 6 magazines + thickness of the 5 sheet of paper
So the thickness of the stack = 120mm + 0.080mm = 120.080mm
Now this can also be written as,
So, the thickness of the stack = $1.20080 \times {10^2}$mm
So this is the required thickness of the stack.
Hence option (B) is the correct answer.

Note – Whenever we face such types of questions the key concept we have to remember is that the thickness of 6 magazines is equal to the product of thickness of one magazine and the number of magazines, and the thickness of 5 sheet of paper is equal to the product of thickness of one sheet of paper and the number of sheet of paper.