Finding the Fourth Proportional to 9,980.31, 13,771.32 and 5,731.56

Step by Step Solution

1. Step 1: Write the proportion equation
   9,980.31 : 13,771.32 = 5,731.56 : x
2. Step 2: Convert to fraction form
   9,980.31/13,771.32 = 5,731.56/x
3. Step 3: Cross multiply
   9,980.31x = 13,771.32 × 5,731.56
4. Step 4: Simplify right side
   9,980.31x = 78,931,146.86
5. Step 5: Solve for x
   x = 78,931,146.86/9,980.31
6. Step 6: Final answer
   x = 7,908.69