I think that you mistyped the numbers regarding this question. Based on some similar questions I have seen, did you mean to say "4 gallons", "6 times" and "215 loads"? If so, here is the solution I came up with and my reasoning.
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We are given the following information:
- The dishwasher in question uses 4 gallons of water per load.
- The advertisement claims that handwashing dishes uses 6 times as much water then the dishwasher being advertised.
- Based on the estimate, we need to determine the amount of gallons that would be saved to wash 215 loads using the dishwasher instead of handwashing them.
This information being given we work through the steps as follows:
1. First, multiply 4 by 215.
×
2. Now, multiply 860 by 6.
×
3. Finally, take 5,160 and subtract it by 860.
Hence, our solution would be
.
Hope this helps!