Finding the Fourth Proportional to 1,978.90, 2,968.68 and 680.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.90 : 2,968.68 = 680.02 : x
2. Step 2: Convert to fraction form
   1,978.90/2,968.68 = 680.02/x
3. Step 3: Cross multiply
   1,978.90x = 2,968.68 × 680.02
4. Step 4: Simplify right side
   1,978.90x = 2,018,761.77
5. Step 5: Solve for x
   x = 2,018,761.77/1,978.90
6. Step 6: Final answer
   x = 1,020.14