Finding the Fourth Proportional to 2,171.31, 3,256.61 and 611.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,171.31 : 3,256.61 = 611.42 : x
2. Step 2: Convert to fraction form
   2,171.31/3,256.61 = 611.42/x
3. Step 3: Cross multiply
   2,171.31x = 3,256.61 × 611.42
4. Step 4: Simplify right side
   2,171.31x = 1,991,156.49
5. Step 5: Solve for x
   x = 1,991,156.49/2,171.31
6. Step 6: Final answer
   x = 917.03