Finding the Fourth Proportional to 2,091.78, 2,887.91 and 1,306.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,091.78 : 2,887.91 = 1,306.89 : x
2. Step 2: Convert to fraction form
   2,091.78/2,887.91 = 1,306.89/x
3. Step 3: Cross multiply
   2,091.78x = 2,887.91 × 1,306.89
4. Step 4: Simplify right side
   2,091.78x = 3,774,174.17
5. Step 5: Solve for x
   x = 3,774,174.17/2,091.78
6. Step 6: Final answer
   x = 1,804.29