Finding the Fourth Proportional to 1,591.14, 2,385.30 and 810.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,591.14 : 2,385.30 = 810.72 : x
2. Step 2: Convert to fraction form
   1,591.14/2,385.30 = 810.72/x
3. Step 3: Cross multiply
   1,591.14x = 2,385.30 × 810.72
4. Step 4: Simplify right side
   1,591.14x = 1,933,810.42
5. Step 5: Solve for x
   x = 1,933,810.42/1,591.14
6. Step 6: Final answer
   x = 1,215.36