Finding the Fourth Proportional to 1,421.31, 1,961.22 and 791.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,421.31 : 1,961.22 = 791.71 : x
2. Step 2: Convert to fraction form
   1,421.31/1,961.22 = 791.71/x
3. Step 3: Cross multiply
   1,421.31x = 1,961.22 × 791.71
4. Step 4: Simplify right side
   1,421.31x = 1,552,717.49
5. Step 5: Solve for x
   x = 1,552,717.49/1,421.31
6. Step 6: Final answer
   x = 1,092.46