Finding the Fourth Proportional to 5,187.57, 7,781.38 and 1,291.98

Step by Step Solution

1. Step 1: Write the proportion equation
   5,187.57 : 7,781.38 = 1,291.98 : x
2. Step 2: Convert to fraction form
   5,187.57/7,781.38 = 1,291.98/x
3. Step 3: Cross multiply
   5,187.57x = 7,781.38 × 1,291.98
4. Step 4: Simplify right side
   5,187.57x = 10,053,387.33
5. Step 5: Solve for x
   x = 10,053,387.33/5,187.57
6. Step 6: Final answer
   x = 1,937.98