Finding the Fourth Proportional to 3,123.77, 4,684.10 and 931.91

Step by Step Solution

1. Step 1: Write the proportion equation
   3,123.77 : 4,684.10 = 931.91 : x
2. Step 2: Convert to fraction form
   3,123.77/4,684.10 = 931.91/x
3. Step 3: Cross multiply
   3,123.77x = 4,684.10 × 931.91
4. Step 4: Simplify right side
   3,123.77x = 4,365,131.55
5. Step 5: Solve for x
   x = 4,365,131.55/3,123.77
6. Step 6: Final answer
   x = 1,397.39