Finding the Fourth Proportional to 1,978.62, 2,968.29 and 679.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.62 : 2,968.29 = 679.80 : x
2. Step 2: Convert to fraction form
   1,978.62/2,968.29 = 679.80/x
3. Step 3: Cross multiply
   1,978.62x = 2,968.29 × 679.80
4. Step 4: Simplify right side
   1,978.62x = 2,017,843.54
5. Step 5: Solve for x
   x = 2,017,843.54/1,978.62
6. Step 6: Final answer
   x = 1,019.82