Finding the Fourth Proportional to 28,300.98, 42,431.34 and 13,299.72

Step by Step Solution

1. Step 1: Write the proportion equation
   28,300.98 : 42,431.34 = 13,299.72 : x
2. Step 2: Convert to fraction form
   28,300.98/42,431.34 = 13,299.72/x
3. Step 3: Cross multiply
   28,300.98x = 42,431.34 × 13,299.72
4. Step 4: Simplify right side
   28,300.98x = 564,324,941.22
5. Step 5: Solve for x
   x = 564,324,941.22/28,300.98
6. Step 6: Final answer
   x = 19,940.12