Finding the Fourth Proportional to 1,877.48, 2,815.76 and 781.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,877.48 : 2,815.76 = 781.25 : x
2. Step 2: Convert to fraction form
   1,877.48/2,815.76 = 781.25/x
3. Step 3: Cross multiply
   1,877.48x = 2,815.76 × 781.25
4. Step 4: Simplify right side
   1,877.48x = 2,199,800.37
5. Step 5: Solve for x
   x = 2,199,800.37/1,877.48
6. Step 6: Final answer
   x = 1,171.68