Finding the Fourth Proportional to 3,778.76, 5,671.67 and 1,931.20

Step by Step Solution

1. Step 1: Write the proportion equation
   3,778.76 : 5,671.67 = 1,931.20 : x
2. Step 2: Convert to fraction form
   3,778.76/5,671.67 = 1,931.20/x
3. Step 3: Cross multiply
   3,778.76x = 5,671.67 × 1,931.20
4. Step 4: Simplify right side
   3,778.76x = 10,953,105.27
5. Step 5: Solve for x
   x = 10,953,105.27/3,778.76
6. Step 6: Final answer
   x = 2,898.60