Grade 12AlgebraThe fourth term of an AP is 4. Then the sum of the first 7 terms is Samir Madan 12 Years agoGrade 12
bharat bajaj12 Years agot4= 4 a + 3d = 4 S7= 3.5 x [2a + 6d] S7= 7 (2)(a+3d) = 7(2)(4) S7= 28Thanks & RegardsBharat Bajajaskiitian facultyIIT Delhi