Question

Write the value of n for which the numbers 3n , 5n+7 and 9n -2 are in A.P.​

Answer 1

Answer:

n=1

STEP BY STEP EXPLANATION:-

let us assume that the given nos. are in ap

Now since,3n, 5n+7 and 9n-2 are in ap

then, their common difference will be same

therefore

5n+7-3n=9n-2-5n+7

2n+7=4n+5

2n=2

n=1

Answer 2

Answer:

Step-by-step explanation:

let  3n=a1, 5n+7=a2, 9n-2=a3

2*a2=a1+a3

2*(5n+7)=3n+9n-2

10n+14=12n-2

 1 4+2=12n-10n

     16=2n

      n=16/2

      n=8