Finding the Fourth Proportional to 1,402.30, 1,935.24 and 812.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,402.30 : 1,935.24 = 812.88 : x
2. Step 2: Convert to fraction form
   1,402.30/1,935.24 = 812.88/x
3. Step 3: Cross multiply
   1,402.30x = 1,935.24 × 812.88
4. Step 4: Simplify right side
   1,402.30x = 1,573,117.89
5. Step 5: Solve for x
   x = 1,573,117.89/1,402.30
6. Step 6: Final answer
   x = 1,121.81