Finding the Fourth Proportional to 2,187.76, 3,002.12 and 1,989.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,187.76 : 3,002.12 = 1,989.76 : x
2. Step 2: Convert to fraction form
   2,187.76/3,002.12 = 1,989.76/x
3. Step 3: Cross multiply
   2,187.76x = 3,002.12 × 1,989.76
4. Step 4: Simplify right side
   2,187.76x = 5,973,498.29
5. Step 5: Solve for x
   x = 5,973,498.29/2,187.76
6. Step 6: Final answer
   x = 2,730.42