Finding the Fourth Proportional to 3,479.10, 5,218.12 and 1,139.34

Step by Step Solution

1. Step 1: Write the proportion equation
   3,479.10 : 5,218.12 = 1,139.34 : x
2. Step 2: Convert to fraction form
   3,479.10/5,218.12 = 1,139.34/x
3. Step 3: Cross multiply
   3,479.10x = 5,218.12 × 1,139.34
4. Step 4: Simplify right side
   3,479.10x = 5,945,219.16
5. Step 5: Solve for x
   x = 5,945,219.16/3,479.10
6. Step 6: Final answer
   x = 1,708.84