Finding the Fourth Proportional to 2,171.34, 3,257.04 and 784.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,171.34 : 3,257.04 = 784.78 : x
2. Step 2: Convert to fraction form
   2,171.34/3,257.04 = 784.78/x
3. Step 3: Cross multiply
   2,171.34x = 3,257.04 × 784.78
4. Step 4: Simplify right side
   2,171.34x = 2,556,059.85
5. Step 5: Solve for x
   x = 2,556,059.85/2,171.34
6. Step 6: Final answer
   x = 1,177.18