Finding the Fourth Proportional to 1,978.28, 2,965.56 and 678.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.28 : 2,965.56 = 678.82 : x
2. Step 2: Convert to fraction form
   1,978.28/2,965.56 = 678.82/x
3. Step 3: Cross multiply
   1,978.28x = 2,965.56 × 678.82
4. Step 4: Simplify right side
   1,978.28x = 2,013,081.44
5. Step 5: Solve for x
   x = 2,013,081.44/1,978.28
6. Step 6: Final answer
   x = 1,017.59