A tank that is 40% full contains 648 gallons of water. Use a double number line to find the maximum capacity of the water tank.

Here is what the numbers would look like on a number line. They are lined up.

10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

162 324 486 648 810 972 1134 1296 1458 1620

The maximum capacity is 1620 gallons of water.