Finding the Fourth Proportional to 1,011.40, 1,395.72 and 591.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,011.40 : 1,395.72 = 591.76 : x
2. Step 2: Convert to fraction form
   1,011.40/1,395.72 = 591.76/x
3. Step 3: Cross multiply
   1,011.40x = 1,395.72 × 591.76
4. Step 4: Simplify right side
   1,011.40x = 825,931.27
5. Step 5: Solve for x
   x = 825,931.27/1,011.40
6. Step 6: Final answer
   x = 816.62