Finding the Fourth Proportional to 1,978.68, 2,731.50 and 1,280.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.68 : 2,731.50 = 1,280.28 : x
2. Step 2: Convert to fraction form
   1,978.68/2,731.50 = 1,280.28/x
3. Step 3: Cross multiply
   1,978.68x = 2,731.50 × 1,280.28
4. Step 4: Simplify right side
   1,978.68x = 3,497,084.82
5. Step 5: Solve for x
   x = 3,497,084.82/1,978.68
6. Step 6: Final answer
   x = 1,767.38