Finding the Fourth Proportional to 5,920.79, 8,168.78 and 3,931.74

Step by Step Solution

1. Step 1: Write the proportion equation
   5,920.79 : 8,168.78 = 3,931.74 : x
2. Step 2: Convert to fraction form
   5,920.79/8,168.78 = 3,931.74/x
3. Step 3: Cross multiply
   5,920.79x = 8,168.78 × 3,931.74
4. Step 4: Simplify right side
   5,920.79x = 32,117,528.91
5. Step 5: Solve for x
   x = 32,117,528.91/5,920.79
6. Step 6: Final answer
   x = 5,424.54