Answer: The answer provided is based on the following calculation:
To make a 75% syrup, Ella should add enough water to the sugar to create a solution that is 25% sugar and 75% water.
To calculate how much water to add, you can use the formula: (desired % of sugar) / (100 - desired % of sugar) * (amount of sugar).
In this case, it would be: (0.75) / (100 - 0.75) * (0.5 lb) = 0.67 lb of water.
To calculate the total amount of syrup, you add the amount of sugar and the amount of water: 0.5 lb + 0.67 lb = 1.17 lb.
So Ella should add 0.67 lb of water to make a 75% syrup and will have a total of 1.17 lb syrup.
Explanation: