Finding the Fourth Proportional to 1,429.90, 2,145.15 and 813.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,429.90 : 2,145.15 = 813.10 : x
2. Step 2: Convert to fraction form
   1,429.90/2,145.15 = 813.10/x
3. Step 3: Cross multiply
   1,429.90x = 2,145.15 × 813.10
4. Step 4: Simplify right side
   1,429.90x = 1,744,221.47
5. Step 5: Solve for x
   x = 1,744,221.47/1,429.90
6. Step 6: Final answer
   x = 1,219.82