Inequality problem algebra? How would I solve the following inequality problem.
$s+1<2s+1<4$
My book answer says $s\in (0, \frac32)$ as the final answer but I cannot seem to get that answer.

You have 2 inequality in 1
1)$s+1<2s+1$ and 
2)$2s+1<4$
Now,you solve first the inequality 1)
$s+1<2s+1$
$0<s$
Then, solve the inequality 2)
$2s+1<4$
$2s<3$
$s<3/2$
Then, you have both, $0<s$ and $s<3/2$, namely $0<s<3/2$ and that's the answer in your book
