Finding the Fourth Proportional to 2,680.83, 4,015.71 and 1,988.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,680.83 : 4,015.71 = 1,988.28 : x
2. Step 2: Convert to fraction form
   2,680.83/4,015.71 = 1,988.28/x
3. Step 3: Cross multiply
   2,680.83x = 4,015.71 × 1,988.28
4. Step 4: Simplify right side
   2,680.83x = 7,984,355.88
5. Step 5: Solve for x
   x = 7,984,355.88/2,680.83
6. Step 6: Final answer
   x = 2,978.31