Question

Sum of first 51 terms if 2nd term is 14 and 3rd is 18

Answer 1

Answer:

Step-by-step explanation:

                a +1 d  =14

subtract   a +2 d =18

                    -1 d  = -4

                       d  =  4

a + 4 = 14   ⇒  a = 10

s = n/2 { 2a + (n-1)d}    ⇒ s = 51/2 { 20 + 200 }    ⇒  s = 5610