Finding the Fourth Proportional to 1,075.72, 1,614.17 and 426.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,075.72 : 1,614.17 = 426.91 : x
2. Step 2: Convert to fraction form
   1,075.72/1,614.17 = 426.91/x
3. Step 3: Cross multiply
   1,075.72x = 1,614.17 × 426.91
4. Step 4: Simplify right side
   1,075.72x = 689,105.31
5. Step 5: Solve for x
   x = 689,105.31/1,075.72
6. Step 6: Final answer
   x = 640.60