Finding the Fourth Proportional to 1,672.57, 2,505.43 and 781.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,672.57 : 2,505.43 = 781.82 : x
2. Step 2: Convert to fraction form
   1,672.57/2,505.43 = 781.82/x
3. Step 3: Cross multiply
   1,672.57x = 2,505.43 × 781.82
4. Step 4: Simplify right side
   1,672.57x = 1,958,793.33
5. Step 5: Solve for x
   x = 1,958,793.33/1,672.57
6. Step 6: Final answer
   x = 1,171.13