Finding the Fourth Proportional to 19,988.98, 30,008.31 and 12,945.94

Step by Step Solution

1. Step 1: Write the proportion equation
   19,988.98 : 30,008.31 = 12,945.94 : x
2. Step 2: Convert to fraction form
   19,988.98/30,008.31 = 12,945.94/x
3. Step 3: Cross multiply
   19,988.98x = 30,008.31 × 12,945.94
4. Step 4: Simplify right side
   19,988.98x = 388,485,780.76
5. Step 5: Solve for x
   x = 388,485,780.76/19,988.98
6. Step 6: Final answer
   x = 19,435.00