Finding the Fourth Proportional to 7,817.31, 10,788.48 and 5,160.12

Step by Step Solution

1. Step 1: Write the proportion equation
   7,817.31 : 10,788.48 = 5,160.12 : x
2. Step 2: Convert to fraction form
   7,817.31/10,788.48 = 5,160.12/x
3. Step 3: Cross multiply
   7,817.31x = 10,788.48 × 5,160.12
4. Step 4: Simplify right side
   7,817.31x = 55,669,851.42
5. Step 5: Solve for x
   x = 55,669,851.42/7,817.31
6. Step 6: Final answer
   x = 7,121.36