Finding the Fourth Proportional to 1,327.91, 1,991.89 and 354.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,327.91 : 1,991.89 = 354.15 : x
2. Step 2: Convert to fraction form
   1,327.91/1,991.89 = 354.15/x
3. Step 3: Cross multiply
   1,327.91x = 1,991.89 × 354.15
4. Step 4: Simplify right side
   1,327.91x = 705,426.07
5. Step 5: Solve for x
   x = 705,426.07/1,327.91
6. Step 6: Final answer
   x = 531.23