Answer:

Step-by-step explanation:

Answer:

5412

Step-by-step explanation:

a(first term)=12

common difference(d)=6

last term(l)=252

formula =

    an=a+(n-1)d

  inputting values

   252=12(n-1)6

   40=n-1

    41=n

    hence total no. of terms = 41

   according to question

    sum of all the terms (sn)=

     formula=  

     sn=n/2(2a+(n-1)d)

     s41=41/2<2(12) +(41-1)6>

     s41=41/2(24+240)

     s41=41*132

      s4=5412

hope this helps ,

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