Finding the Fourth Proportional to 1,402.63, 1,935.21 and 813.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,402.63 : 1,935.21 = 813.15 : x
2. Step 2: Convert to fraction form
   1,402.63/1,935.21 = 813.15/x
3. Step 3: Cross multiply
   1,402.63x = 1,935.21 × 813.15
4. Step 4: Simplify right side
   1,402.63x = 1,573,616.01
5. Step 5: Solve for x
   x = 1,573,616.01/1,402.63
6. Step 6: Final answer
   x = 1,121.90