In 1995, the Johnsons spent $800 on the family’s water bills. Anticipating that water rates would increase in 1996 by 50%, the Johnsons cut back their water usage. By how much must the Johnsons have reduced their 1996 water usage to pay exactly the same amount in 1996 as they paid in 1995?
Choose the correct choice from the following choices:
A) 33 1⁄3%
B) 40%
C) 50%
D) 66 2⁄3%
E) 100%
In 1995 , water usage for Johnson's = w   and cost per unit of water = c   cw = 800   =&gt; w=800/c -- 1   In 1996 , cost per unit of water = 1.5 c   Water usage for Johnson's so as to pay same amount as in 1995= w'   1.5c * w' = 800   =&gt; w' = 800/1.5c   =&gt; w' = (2/3c)*800   From 1 and 2 , we get   w' = 2/3 w   (w-w')/w = 1/3   33 1⁄3%nswer 33 1⁄3%
<result>A</result>
In 1995, the Johnsons spent $800 on the family’s water bills. Anticipating that water rates would increase in 1996 by 50%, the Johnsons cut back their water usage. By how much must the Johnsons have reduced their 1996 water usage to pay exactly the same amount in 1996 as they paid in 1995?