Finding the Fourth Proportional to 2,171.35, 3,256.17 and 784.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,171.35 : 3,256.17 = 784.72 : x
2. Step 2: Convert to fraction form
   2,171.35/3,256.17 = 784.72/x
3. Step 3: Cross multiply
   2,171.35x = 3,256.17 × 784.72
4. Step 4: Simplify right side
   2,171.35x = 2,555,181.72
5. Step 5: Solve for x
   x = 2,555,181.72/2,171.35
6. Step 6: Final answer
   x = 1,176.77