TheCATExam
Sign in

CAT 1994 — QA Question 12

Two Quadratic EquationsEasy
Passage / Data

Answer the next 3 questions based on the information given below:

Ghoshbabu is staying at Ghosh Housing Society, Aghosh Colony, Dighospur, Calcutta. In Ghosh Housing Society 6 persons read daily Ganashakti and 4 read Anand Bazar Patrika; in his colony there is no person who reads both. Total number of persons who read these two newspapers in Aghosh Colony and Dighospur is 52 and 200 respectively. Number of persons who read Ganashakti in Aghosh Colony and Dighospur is 33 and 121 respectively; while the persons who read Anand Bazar Patrika in Aghosh Colony and Dighospur are 32 and 117 respectively.

If one root of x2 − px + 12 = 0 is 4, while the equation x2 − px + q = 0 has equal roots, then the value of q is

Answer & solution

  • 494

  • B

    449

  • C

    4

  • D

    14

Solution

If one root of x2 + px + 12 = 0 is 4, then 42 + 4p + 12 = 0, i.e. p = –7.

x2 – px + q = 0 has equal roots.

If the roots are α each, 2α = - (-7)1 = 7, i.e., α = 72, and q = α2

⇒q=494

Hence, option (a).

CAT 1994 QA Q12: If one root of x 2 − px + 12 = 0 is 4, while the equation x 2 − px + q = 0 has equal roots, then t — Solution | TheCATExam