Finding the Fourth Proportional to 2,139.48, 3,210.84 and 986.04

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.48 : 3,210.84 = 986.04 : x
2. Step 2: Convert to fraction form
   2,139.48/3,210.84 = 986.04/x
3. Step 3: Cross multiply
   2,139.48x = 3,210.84 × 986.04
4. Step 4: Simplify right side
   2,139.48x = 3,166,016.67
5. Step 5: Solve for x
   x = 3,166,016.67/2,139.48
6. Step 6: Final answer
   x = 1,479.81