Finding the Fourth Proportional to 7,766.28, 10,721.88 and 5,118.30

Step by Step Solution

1. Step 1: Write the proportion equation
   7,766.28 : 10,721.88 = 5,118.30 : x
2. Step 2: Convert to fraction form
   7,766.28/10,721.88 = 5,118.30/x
3. Step 3: Cross multiply
   7,766.28x = 10,721.88 × 5,118.30
4. Step 4: Simplify right side
   7,766.28x = 54,877,820.68
5. Step 5: Solve for x
   x = 54,877,820.68/7,766.28
6. Step 6: Final answer
   x = 7,066.17