Finding the Fourth Proportional to 2,421.56, 3,631.86 and 689.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,421.56 : 3,631.86 = 689.78 : x
2. Step 2: Convert to fraction form
   2,421.56/3,631.86 = 689.78/x
3. Step 3: Cross multiply
   2,421.56x = 3,631.86 × 689.78
4. Step 4: Simplify right side
   2,421.56x = 2,505,184.39
5. Step 5: Solve for x
   x = 2,505,184.39/2,421.56
6. Step 6: Final answer
   x = 1,034.53