Finding the Fourth Proportional to 28,008.04, 42,006.18 and 12,415.72

Step by Step Solution

1. Step 1: Write the proportion equation
   28,008.04 : 42,006.18 = 12,415.72 : x
2. Step 2: Convert to fraction form
   28,008.04/42,006.18 = 12,415.72/x
3. Step 3: Cross multiply
   28,008.04x = 42,006.18 × 12,415.72
4. Step 4: Simplify right side
   28,008.04x = 521,536,969.15
5. Step 5: Solve for x
   x = 521,536,969.15/28,008.04
6. Step 6: Final answer
   x = 18,620.97