Finding the Fourth Proportional to 42,009.50, 63,026.54 and 12,428.10

Step by Step Solution

1. Step 1: Write the proportion equation
   42,009.50 : 63,026.54 = 12,428.10 : x
2. Step 2: Convert to fraction form
   42,009.50/63,026.54 = 12,428.10/x
3. Step 3: Cross multiply
   42,009.50x = 63,026.54 × 12,428.10
4. Step 4: Simplify right side
   42,009.50x = 783,300,126.24
5. Step 5: Solve for x
   x = 783,300,126.24/42,009.50
6. Step 6: Final answer
   x = 18,645.78