Finding the Fourth Proportional to 20,139, 30,112.38 and 18,374.46

Step by Step Solution

1. Step 1: Write the proportion equation
   20,139 : 30,112.38 = 18,374.46 : x
2. Step 2: Convert to fraction form
   20,139/30,112.38 = 18,374.46/x
3. Step 3: Cross multiply
   20,139x = 30,112.38 × 18,374.46
4. Step 4: Simplify right side
   20,139x = 553,298,721.81
5. Step 5: Solve for x
   x = 553,298,721.81/20,139
6. Step 6: Final answer
   x = 27,473.99