CAT 1994QA Question 42

Data SufficiencyEasy
Passage / Data

Each of these items has a question followed by two statements. As the answer,

Mark (a), If the question can be answered with the help of statement I alone,
Mark (b), If the question can be answered with the help of statement II, alone,
Mark (c), If both, statement I and statement II are needed to answer the question, and
Mark (d), If the question cannot be answered even with the help of both the statements.

A and B work at digging a ditch alternately for a day each. If A can dig a ditch in ‘a’ days and B can dig that ditch in ‘b’ days, will work get done faster if A begins the work?
I. n is a positive integer such that n(1a+1b) = 1

II. b > a

Answer & solution

  • a

  • B

    b

  • C

    c

  • D

    d

Solution

If the total work is one unit, work done by A and B in one day will be 1a unit and 1b unit respectively.
Using statement I: na+nb = 1,

Since ‘n’ is an integer, if both A and B work for n days, work will be completed no matter who starts a work.

Using statement II, nothing can be concluded as total amount of work is not known.

CAT 1994 QA Q42: A and B work at digging a ditch alternately for a day each. If A can dig a ditch in ‘a’ days and B — Solution | TheCATExam