Question

the first term of an arithmetic sequence is -2 and the fifteenth term is 68. what is the common difference of the sequence? 7 33/8 5

Answer 1

Hello,

Answer C : 5


`u_(1)=-2\\ u_(2)=-2+r\\ u_(3)=-2+2r\\ u_(15)=-2+14r=68\\`
==>14r-2=68
==>14r=70
==>r=5