Finding the Fourth Proportional to 1,429.31, 1,972.76 and 905.65

Step by Step Solution

1. Step 1: Write the proportion equation
   1,429.31 : 1,972.76 = 905.65 : x
2. Step 2: Convert to fraction form
   1,429.31/1,972.76 = 905.65/x
3. Step 3: Cross multiply
   1,429.31x = 1,972.76 × 905.65
4. Step 4: Simplify right side
   1,429.31x = 1,786,620.63
5. Step 5: Solve for x
   x = 1,786,620.63/1,429.31
6. Step 6: Final answer
   x = 1,249.99