To avoid the excessive use of water, the water control office started increases in the "C" costs, in dollars of the tariffs, depending on the number of "X" cubic meters of water consumed
Solve:
The cost in dollars, for a consumption of 15 cubic meters of water.
The cost in dollars, for a consumption of 30 cubic meters of water.
The cost in dollars, for a consumption of 50 cubic meters of water.
The cost in dollars, for a consumption of 70 cubic meters of water.