Finding the Fourth Proportional to 2,165.86, 2,989.88 and 1,380.98

Step by Step Solution

1. Step 1: Write the proportion equation
   2,165.86 : 2,989.88 = 1,380.98 : x
2. Step 2: Convert to fraction form
   2,165.86/2,989.88 = 1,380.98/x
3. Step 3: Cross multiply
   2,165.86x = 2,989.88 × 1,380.98
4. Step 4: Simplify right side
   2,165.86x = 4,128,964.48
5. Step 5: Solve for x
   x = 4,128,964.48/2,165.86
6. Step 6: Final answer
   x = 1,906.39