Finding the Fourth Proportional to 19,931.56, 27,505.43 and 10,978.86

Step by Step Solution

1. Step 1: Write the proportion equation
   19,931.56 : 27,505.43 = 10,978.86 : x
2. Step 2: Convert to fraction form
   19,931.56/27,505.43 = 10,978.86/x
3. Step 3: Cross multiply
   19,931.56x = 27,505.43 × 10,978.86
4. Step 4: Simplify right side
   19,931.56x = 301,978,072.79
5. Step 5: Solve for x
   x = 301,978,072.79/19,931.56
6. Step 6: Final answer
   x = 15,150.75