Finding the Fourth Proportional to 1,426.10, 2,139.15 and 452.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,426.10 : 2,139.15 = 452.30 : x
2. Step 2: Convert to fraction form
   1,426.10/2,139.15 = 452.30/x
3. Step 3: Cross multiply
   1,426.10x = 2,139.15 × 452.30
4. Step 4: Simplify right side
   1,426.10x = 967,537.55
5. Step 5: Solve for x
   x = 967,537.55/1,426.10
6. Step 6: Final answer
   x = 678.45