Finding the Fourth Proportional to 2,079.40, 2,865.36 and 1,978.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,079.40 : 2,865.36 = 1,978.96 : x
2. Step 2: Convert to fraction form
   2,079.40/2,865.36 = 1,978.96/x
3. Step 3: Cross multiply
   2,079.40x = 2,865.36 × 1,978.96
4. Step 4: Simplify right side
   2,079.40x = 5,670,432.83
5. Step 5: Solve for x
   x = 5,670,432.83/2,079.40
6. Step 6: Final answer
   x = 2,726.96