Finding the Fourth Proportional to 2,152.78, 3,228.86 and 691.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,152.78 : 3,228.86 = 691.74 : x
2. Step 2: Convert to fraction form
   2,152.78/3,228.86 = 691.74/x
3. Step 3: Cross multiply
   2,152.78x = 3,228.86 × 691.74
4. Step 4: Simplify right side
   2,152.78x = 2,233,533.35
5. Step 5: Solve for x
   x = 2,233,533.35/2,152.78
6. Step 6: Final answer
   x = 1,037.51