Finding the Fourth Proportional to 1,328.42, 1,991.82 and 548.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,328.42 : 1,991.82 = 548.18 : x
2. Step 2: Convert to fraction form
   1,328.42/1,991.82 = 548.18/x
3. Step 3: Cross multiply
   1,328.42x = 1,991.82 × 548.18
4. Step 4: Simplify right side
   1,328.42x = 1,091,875.89
5. Step 5: Solve for x
   x = 1,091,875.89/1,328.42
6. Step 6: Final answer
   x = 821.94