Example

Water used (in thousands of gallons)	Cost
$0\leq x\leq 10$	$$9.00$
$10\lt x\leq 30$	$$9.00+0.95$ for each thousand gallons in excess of $10{,}000$ gallons
$30\lt x\leq 100$	$$28.00+1.65$ for each thousand gallons in excess of $30{,}000$ gallons
$x>100$	$$143.50+2.20$ for each thousand gallons in excess of $100{,}000$ gallons

Water used (in thousands of gallons)	Cost
\(0\leq x\leq 10\)	\($9.00\)
\(10\lt x\leq 30\)	\($9.00+0.95\) for each thousand gallons in excess of \(10{,}000\) gallons
\(30\lt x\leq 100\)	\($28.00+1.65\) for each thousand gallons in excess of \(30{,}000\) gallons
\(x>100\)	\($143.50+2.20\) for each thousand gallons in excess of \(100{,}000\) gallons