Finding the Fourth Proportional to 2,221.76, 3,065.04 and 1,289.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,221.76 : 3,065.04 = 1,289.72 : x
2. Step 2: Convert to fraction form
   2,221.76/3,065.04 = 1,289.72/x
3. Step 3: Cross multiply
   2,221.76x = 3,065.04 × 1,289.72
4. Step 4: Simplify right side
   2,221.76x = 3,953,043.39
5. Step 5: Solve for x
   x = 3,953,043.39/2,221.76
6. Step 6: Final answer
   x = 1,779.24