Finding the Fourth Proportional to 42,471.20, 58,618.38 and 28,131.20

Step by Step Solution

1. Step 1: Write the proportion equation
   42,471.20 : 58,618.38 = 28,131.20 : x
2. Step 2: Convert to fraction form
   42,471.20/58,618.38 = 28,131.20/x
3. Step 3: Cross multiply
   42,471.20x = 58,618.38 × 28,131.20
4. Step 4: Simplify right side
   42,471.20x = 1,649,005,371.46
5. Step 5: Solve for x
   x = 1,649,005,371.46/42,471.20
6. Step 6: Final answer
   x = 38,826.44