Finding the Fourth Proportional to 5,111.76, 7,660.05 and 2,643.29

Step by Step Solution

1. Step 1: Write the proportion equation
   5,111.76 : 7,660.05 = 2,643.29 : x
2. Step 2: Convert to fraction form
   5,111.76/7,660.05 = 2,643.29/x
3. Step 3: Cross multiply
   5,111.76x = 7,660.05 × 2,643.29
4. Step 4: Simplify right side
   5,111.76x = 20,247,714.08
5. Step 5: Solve for x
   x = 20,247,714.08/5,111.76
6. Step 6: Final answer
   x = 3,961.00