Finding the Fourth Proportional to 5,686.64, 7,844.56 and 3,915.18

Step by Step Solution

1. Step 1: Write the proportion equation
   5,686.64 : 7,844.56 = 3,915.18 : x
2. Step 2: Convert to fraction form
   5,686.64/7,844.56 = 3,915.18/x
3. Step 3: Cross multiply
   5,686.64x = 7,844.56 × 3,915.18
4. Step 4: Simplify right side
   5,686.64x = 30,712,864.42
5. Step 5: Solve for x
   x = 30,712,864.42/5,686.64
6. Step 6: Final answer
   x = 5,400.88