Finding the Fourth Proportional to 1,991.10, 2,986.25 and 1,892.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,991.10 : 2,986.25 = 1,892.31 : x
2. Step 2: Convert to fraction form
   1,991.10/2,986.25 = 1,892.31/x
3. Step 3: Cross multiply
   1,991.10x = 2,986.25 × 1,892.31
4. Step 4: Simplify right side
   1,991.10x = 5,650,900.72
5. Step 5: Solve for x
   x = 5,650,900.72/1,991.10
6. Step 6: Final answer
   x = 2,838.08