Finding the Fourth Proportional to 1,312.02, 1,809.72 and 787.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,312.02 : 1,809.72 = 787.50 : x
2. Step 2: Convert to fraction form
   1,312.02/1,809.72 = 787.50/x
3. Step 3: Cross multiply
   1,312.02x = 1,809.72 × 787.50
4. Step 4: Simplify right side
   1,312.02x = 1,425,154.50
5. Step 5: Solve for x
   x = 1,425,154.50/1,312.02
6. Step 6: Final answer
   x = 1,086.23