Finding the Fourth Proportional to 72,870.99, 109,313.72 and 20,280.47

Step by Step Solution

1. Step 1: Write the proportion equation
   72,870.99 : 109,313.72 = 20,280.47 : x
2. Step 2: Convert to fraction form
   72,870.99/109,313.72 = 20,280.47/x
3. Step 3: Cross multiply
   72,870.99x = 109,313.72 × 20,280.47
4. Step 4: Simplify right side
   72,870.99x = 2,216,932,971.08
5. Step 5: Solve for x
   x = 2,216,932,971.08/72,870.99
6. Step 6: Final answer
   x = 30,422.71