Finding the Fourth Proportional to 1,209.12, 1,809.72 and 798.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.12 : 1,809.72 = 798.72 : x
2. Step 2: Convert to fraction form
   1,209.12/1,809.72 = 798.72/x
3. Step 3: Cross multiply
   1,209.12x = 1,809.72 × 798.72
4. Step 4: Simplify right side
   1,209.12x = 1,445,459.56
5. Step 5: Solve for x
   x = 1,445,459.56/1,209.12
6. Step 6: Final answer
   x = 1,195.46