Finding the Fourth Proportional to 9,980.27, 13,772.30 and 5,728.38

Step by Step Solution

1. Step 1: Write the proportion equation
   9,980.27 : 13,772.30 = 5,728.38 : x
2. Step 2: Convert to fraction form
   9,980.27/13,772.30 = 5,728.38/x
3. Step 3: Cross multiply
   9,980.27x = 13,772.30 × 5,728.38
4. Step 4: Simplify right side
   9,980.27x = 78,892,967.87
5. Step 5: Solve for x
   x = 78,892,967.87/9,980.27
6. Step 6: Final answer
   x = 7,904.89