Finding the Fourth Proportional to 1,421.06, 1,961.04 and 791.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,421.06 : 1,961.04 = 791.57 : x
2. Step 2: Convert to fraction form
   1,421.06/1,961.04 = 791.57/x
3. Step 3: Cross multiply
   1,421.06x = 1,961.04 × 791.57
4. Step 4: Simplify right side
   1,421.06x = 1,552,300.43
5. Step 5: Solve for x
   x = 1,552,300.43/1,421.06
6. Step 6: Final answer
   x = 1,092.35