Question

2 अंको वाली कि तनी शंखया 3से विभाज हैं

Answer 1

first two digit number which is exactly divisible by 3 =12,

similarly 2nd and 3rd number will be 15 and 18.
greatest two digit number which is exactly divisible by 3 is 99 .

which forms an A.P

12,15,18,............,99

here
a=12, d=3, tn=99,

tn=a+(n-1)d,

99=12+(n-1)×3,

99-12=(n-1)×3,

87=(n-1)×3,

therefore

(n-1)=87/3,

(n-1)=29,

then

n=29+1,

n=30