Banner 0
Banner 1
Banner 2
Banner 3
Banner 4
Banner 5
Banner 6
Banner 7
Banner 8
Banner 9

Q.

STATEMENT 1: The number of ways in which three distinct numbers can be selected from the set {31,32,33,....3100,3101,} so that they form a G. P. is 2500.

STATEMENT 2: If a, b, c are in A.P., then 3a,3b,3c are in G.P.

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.
An Intiative by Sri Chaitanya

a

Both the statement are TRUE and statement 2 is the correct explanation of statement1.
 

b

Both the statements are TRUE but statement 2 is NOT the correct explanation of statement 1.

c

Statement 1 is TRUE and statement 2 is FALSE

d

Statement 1 is FALSE and statement 2 is TRUE

answer is A.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

JEE

NEET

NEET

Foundation JEE

Foundation JEE

Foundation NEET

Foundation NEET

CBSE

CBSE

Detailed Solution

Sol: Statement 2 is correct as when 3a,3b,3c are in G.P., we have (3b)2=(3a)(3c)2b=a+ca,b,c are in A.P. Thus, selecting three numbers in G.P. from {31,32,33,...,3100} is equivalent to selecting 3 numbers from {1,2,3,...,101} which are in A.P. Now, a,b,c are in A.P. if either a  and  c are odd or a  and  c are even.

Number of selection ways of 2 odd numbers is  51C2.

Number of selection ways of 2 even numbers is  50C2.

Hence, total number of ways is  51C2+50C2=1275+1225=2500.

Watch 3-min video & get full concept clarity
score_test_img

courses

No courses found

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Get Expert Academic Guidance – Connect with a Counselor Today!

best study material, now at your finger tips!

  • promsvg

    live classes

  • promsvg

    progress tracking

  • promsvg

    24x7 mentored guidance

  • promsvg

    study plan analysis

download the app

gplay
mentor

Download the App

gplay
whats app icon
personalised 1:1 online tutoring