Finding the Fourth Proportional to 1,929.72, 2,889.89 and 1,311.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,929.72 : 2,889.89 = 1,311.55 : x
2. Step 2: Convert to fraction form
   1,929.72/2,889.89 = 1,311.55/x
3. Step 3: Cross multiply
   1,929.72x = 2,889.89 × 1,311.55
4. Step 4: Simplify right side
   1,929.72x = 3,790,235.23
5. Step 5: Solve for x
   x = 3,790,235.23/1,929.72
6. Step 6: Final answer
   x = 1,964.14