Finding the Fourth Proportional to 12,991.93, 19,486.27 and 5,200.81

Step by Step Solution

1. Step 1: Write the proportion equation
   12,991.93 : 19,486.27 = 5,200.81 : x
2. Step 2: Convert to fraction form
   12,991.93/19,486.27 = 5,200.81/x
3. Step 3: Cross multiply
   12,991.93x = 19,486.27 × 5,200.81
4. Step 4: Simplify right side
   12,991.93x = 101,344,387.88
5. Step 5: Solve for x
   x = 101,344,387.88/12,991.93
6. Step 6: Final answer
   x = 7,800.56