Finding the Fourth Proportional to 20,947.75, 31,436.62 and 7,620.72

Step by Step Solution

1. Step 1: Write the proportion equation
   20,947.75 : 31,436.62 = 7,620.72 : x
2. Step 2: Convert to fraction form
   20,947.75/31,436.62 = 7,620.72/x
3. Step 3: Cross multiply
   20,947.75x = 31,436.62 × 7,620.72
4. Step 4: Simplify right side
   20,947.75x = 239,569,659.71
5. Step 5: Solve for x
   x = 239,569,659.71/20,947.75
6. Step 6: Final answer
   x = 11,436.54