Finding the Fourth Proportional to 1,253.81, 1,729.67 and 811.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,253.81 : 1,729.67 = 811.86 : x
2. Step 2: Convert to fraction form
   1,253.81/1,729.67 = 811.86/x
3. Step 3: Cross multiply
   1,253.81x = 1,729.67 × 811.86
4. Step 4: Simplify right side
   1,253.81x = 1,404,249.89
5. Step 5: Solve for x
   x = 1,404,249.89/1,253.81
6. Step 6: Final answer
   x = 1,119.99