d Question 11 & 12 | Job Exam Rare Mathematics (JEMrare) - Solved MCQs

# Question 11 & 12

Question 11: 1 millimetre thick paper if folded 50 times then find the thickness of the fold.

Solution:

We know

and

or

or

So, we can other way say that;

so, 1 millimeter is equal to 0.000001 kilometer

or we can say that single paper is 0.000001 km thick

If we fold this paper one time then there will be two layers of papers;

One time folding

times of 0.000001

Second time folding, (there will be four layers of papers)

Third time folding ( there will be 8 layers of papers)

Fourth time folding (there will be 16 layers of paper)

,,,,,,,,,,,,,,,,,,,,,, so on ,,,,,,,,,,,,,,,,,,>,,,,,,,,,,,,,,,,,so on,,,,,,,,,,,,,,,,,,,>,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,>,,,,,,,,, so on ,,,,,,,,,,,,,,,,,,,,,,,,>,,,,,,,,,,,,,,,,,,,,,,,,,,,, till

Fiftieth time folding

Now let’s evaluate the term  =

So, if a paper of 1 mm thickness is folded 50 times  then it’s thickness will be equal to 11258999906.842624 kilometers

Or 112 billion kms approximately

Question 12: Total age of 3 men if added is 80 years. What was the sum three years ago?

Solution:

Let there be three persons A, B and C and their ages at present be x, y and z, Then according to the given condition;

Three years ago the ages of A, B and C was x-3, y-3 and z-3 respectively. Now the sum of ages three years ago will be;

Now let us simplify this term;

Sum of ages three years ago =

Putting value of x+y+z from eq (1)

So sum of ages three years ago is 71