Question

plz answer this it is important

Answer 1

Answer:

a=3

d=12

T21= 3+20(12)

= 3+ 240 = 243

term having 120 more than T12 =243+120=363

Tn = 636=3+ (n-1)12

so n-1 =600/12 = 50

so n= 51

Answer 2

SOLUTION:-

Explanation

a= 3

d= 15-3=12

21st term is given by

a21= a+(n-1)×12

= 3+(21-1)×12

= 3+20×12

= 3+ 240

= 243

Required term = 243+120

= 363

Let the nth term

a+(n-1)×d=363

= 3+(n-1)×12= 363

= n-1= 363/12-3

n-1= 360/12

n-1= 30

n= 30+1

n=31

31st term is the required term