To compare the prices of the pavers, we need to calculate the cost of the same quantity for each paver type.
Let's assume Laila needs x number of paver 3 stones.
According to the given information, she will need 2x number of paver 2 stones.
And she will need (1/2)x number of paver 3 stones.
The total cost for paver 1 stones will be 1.49 * (1/2)x = 0.745x.
The total cost for paver 2 stones will be 2.50 * 2x = 5x.
The total cost for paver 3 stones will be 0.75 * x = 0.75x.
Now we can compare the costs:
For paver 1, the cost is 0.745x.
For paver 2, the cost is 5x.
For paver 3, the cost is 0.75x.
Comparing the costs, we can see that paver 1 has the lowest cost. So paver 1 is the best buy.
The answer is $0.745.