Finding the Fourth Proportional to 10,138.72, 13,991.50 and 5,662.87

Step by Step Solution

1. Step 1: Write the proportion equation
   10,138.72 : 13,991.50 = 5,662.87 : x
2. Step 2: Convert to fraction form
   10,138.72/13,991.50 = 5,662.87/x
3. Step 3: Cross multiply
   10,138.72x = 13,991.50 × 5,662.87
4. Step 4: Simplify right side
   10,138.72x = 79,232,045.61
5. Step 5: Solve for x
   x = 79,232,045.61/10,138.72
6. Step 6: Final answer
   x = 7,814.80