Question

answer this question pleasa
it is urgent​

Answer 1

Answer:

Sn = n/2 {2a + (n-1)d}

Sn = 27/2 { 12 + 26(3) }

Sn = 27/2 × ( 12 + 78 )

Sn = 27/2 × 90

Sn = 27 × 45

Sn = 1,215