Finding the Fourth Proportional to 2,551.41, 3,826.31 and 991.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,551.41 : 3,826.31 = 991.31 : x
2. Step 2: Convert to fraction form
   2,551.41/3,826.31 = 991.31/x
3. Step 3: Cross multiply
   2,551.41x = 3,826.31 × 991.31
4. Step 4: Simplify right side
   2,551.41x = 3,793,035.28
5. Step 5: Solve for x
   x = 3,793,035.28/2,551.41
6. Step 6: Final answer
   x = 1,486.64