Finding the Fourth Proportional to 7,721.86, 10,656.15 and 4,185.10

Step by Step Solution

1. Step 1: Write the proportion equation
   7,721.86 : 10,656.15 = 4,185.10 : x
2. Step 2: Convert to fraction form
   7,721.86/10,656.15 = 4,185.10/x
3. Step 3: Cross multiply
   7,721.86x = 10,656.15 × 4,185.10
4. Step 4: Simplify right side
   7,721.86x = 44,597,053.37
5. Step 5: Solve for x
   x = 44,597,053.37/7,721.86
6. Step 6: Final answer
   x = 5,775.43