Finding the Fourth Proportional to 3,430.76, 5,145.83 and 931.85

Step by Step Solution

1. Step 1: Write the proportion equation
   3,430.76 : 5,145.83 = 931.85 : x
2. Step 2: Convert to fraction form
   3,430.76/5,145.83 = 931.85/x
3. Step 3: Cross multiply
   3,430.76x = 5,145.83 × 931.85
4. Step 4: Simplify right side
   3,430.76x = 4,795,111.30
5. Step 5: Solve for x
   x = 4,795,111.30/3,430.76
6. Step 6: Final answer
   x = 1,397.68