Question

The first term of an arithmetic sequence is -5 , and the twelfth term is 1.7 .find the common difference

Answer 1

a=-5
a12 = 1.7

a12 = a+(n-1)d
1.7 = -5+(12-1)d

1.7+5 = 11d

6.7/11 = d
0.60 = d