Finding the Fourth Proportional to 31,002.19, 42,804.15 and 20,808.51

Step by Step Solution

1. Step 1: Write the proportion equation
   31,002.19 : 42,804.15 = 20,808.51 : x
2. Step 2: Convert to fraction form
   31,002.19/42,804.15 = 20,808.51/x
3. Step 3: Cross multiply
   31,002.19x = 42,804.15 × 20,808.51
4. Step 4: Simplify right side
   31,002.19x = 890,690,583.32
5. Step 5: Solve for x
   x = 890,690,583.32/31,002.19
6. Step 6: Final answer
   x = 28,729.92