Question

the 4th term of an ap is 3 times the first and the Seven terms exceeds twice the third term buy 1. find the first term at the common difference

Answer 1

a4=a+3d
a+3d=3a
2a=3d
a=3/2d
a7=a+6d
a+6d+1=a+2d
4d=-1
d=-1/4
a=3/2×-1/4
a=-3/8