Finding the Fourth Proportional to 1,789.48, 2,682.96 and 678.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,789.48 : 2,682.96 = 678.72 : x
2. Step 2: Convert to fraction form
   1,789.48/2,682.96 = 678.72/x
3. Step 3: Cross multiply
   1,789.48x = 2,682.96 × 678.72
4. Step 4: Simplify right side
   1,789.48x = 1,820,978.61
5. Step 5: Solve for x
   x = 1,820,978.61/1,789.48
6. Step 6: Final answer
   x = 1,017.60