Finding the Fourth Proportional to 1,979.18, 2,732.20 and 1,280.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,979.18 : 2,732.20 = 1,280.78 : x
2. Step 2: Convert to fraction form
   1,979.18/2,732.20 = 1,280.78/x
3. Step 3: Cross multiply
   1,979.18x = 2,732.20 × 1,280.78
4. Step 4: Simplify right side
   1,979.18x = 3,499,347.12
5. Step 5: Solve for x
   x = 3,499,347.12/1,979.18
6. Step 6: Final answer
   x = 1,768.08