Finding the Fourth Proportional to 3,404.30, 5,105.10 and 1,211.90

Step by Step Solution

1. Step 1: Write the proportion equation
   3,404.30 : 5,105.10 = 1,211.90 : x
2. Step 2: Convert to fraction form
   3,404.30/5,105.10 = 1,211.90/x
3. Step 3: Cross multiply
   3,404.30x = 5,105.10 × 1,211.90
4. Step 4: Simplify right side
   3,404.30x = 6,186,870.69
5. Step 5: Solve for x
   x = 6,186,870.69/3,404.30
6. Step 6: Final answer
   x = 1,817.37