Finding the Fourth Proportional to 1,871.58, 2,806.20 and 831.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,871.58 : 2,806.20 = 831.54 : x
2. Step 2: Convert to fraction form
   1,871.58/2,806.20 = 831.54/x
3. Step 3: Cross multiply
   1,871.58x = 2,806.20 × 831.54
4. Step 4: Simplify right side
   1,871.58x = 2,333,467.55
5. Step 5: Solve for x
   x = 2,333,467.55/1,871.58
6. Step 6: Final answer
   x = 1,246.79