OEIt is given that an 18 pages long book comprises either of 3 pages or 4 pages long
chapters.
We have to compare
Quantity A: The number of chapters with 3 pages
Quantity B: The number of chapters with 4 pages
Let us assume that the number 3 pages and 4 pages chapters in the book is 𝑥 and 𝑦
respectively.
Then we have, 3𝑥 + 4𝑦 = 18
Taking 𝑥 in terms of 𝑦, we get
x=18-4y/3 (equation 1)
Since, the number of pages cannot be in decimals or fractions so we need to find an
integer solution for eqn.1
Also, we can see that 18 – 4𝑦 should be a multiple of 3 to give integer value for 𝑥.
So, let us put value for 𝑦 and check if we are getting a positive integer for 𝑥.
If y=1, x=14/3 which is not an integer value.
Similarly, if 𝑦 = 2, 𝑥 = 10/3 which is not an integer value.
If y=3 x=6/3=2
which is an integer value.
So, we can see that 𝑥 = 2, 𝑦 = 3 is an integer solution for eqn.1
Now, if we take 𝑦 = 4 x=2/3 which is not an integer.
If we take 𝑦 > 4 then we will get 𝑥 < 0 which can’t be true.
Hence, the only integer solution we are getting for eqn.1 is 𝑥 = 2 and 𝑦 = 3.
So, Quantity A is 2 and Quantity B is 3.
Clearly, Quantity B is greater.
Ans. B
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