Maths : Basic Numeracy

Q 171 / 370

UPSC CSE Prelims 2021

Jay and Vijay spent an equal amount of money to buy some pens and special pencils of the same quality from the same store, If Jay bought 3 pens and 5 pencils, and Vijay bought 2 pens and 7 pencils, then which one of the following is correct?

EXPLANATION

Correct Option

Let Ppen represent the price of one pen and Ppencil represent the price of one pencil.

According to the problem statement, Jay and Vijay spent an equal amount of money.

  • Jay's total expenditure: 3×Ppen+5×Ppencil
  • Vijay's total expenditure: 2×Ppen+7×Ppencil

Equating their expenditures:

3×Ppen+5×Ppencil=2×Ppen+7×Ppencil

Rearranging the terms to determine the relationship between the prices:

3×Ppen−2×Ppen=7×Ppencil−5×Ppencil

Ppen=2×Ppencil

This equation indicates that the price of a pen is two times the price of a pencil.

Incorrect Options

  • A pencil costs more than a pen:

    The derived relationship Ppen=2×Ppencil implies that Ppencil=0.5×Ppen. Therefore, a pencil costs half the price of a pen, making this statement incorrect.

  • The price of a pen is two times the price of a pencil:

    This statement is identical to Option 2, which is the correct answer. In a standard multiple-choice question, only one option is designated as the primary correct answer.

  • The price of a pen is three times the Price of a pencil:

    The calculation establishes that Ppen=2×Ppencil, not three times. Hence, this statement is incorrect.