Finding the Fourth Proportional to 13,385.44, 18,470.59 and 7,720.71

Step by Step Solution

1. Step 1: Write the proportion equation
   13,385.44 : 18,470.59 = 7,720.71 : x
2. Step 2: Convert to fraction form
   13,385.44/18,470.59 = 7,720.71/x
3. Step 3: Cross multiply
   13,385.44x = 18,470.59 × 7,720.71
4. Step 4: Simplify right side
   13,385.44x = 142,606,068.92
5. Step 5: Solve for x
   x = 142,606,068.92/13,385.44
6. Step 6: Final answer
   x = 10,653.82