Finding the Fourth Proportional to 1,328.10, 1,990.82 and 548.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,328.10 : 1,990.82 = 548.67 : x
2. Step 2: Convert to fraction form
   1,328.10/1,990.82 = 548.67/x
3. Step 3: Cross multiply
   1,328.10x = 1,990.82 × 548.67
4. Step 4: Simplify right side
   1,328.10x = 1,092,300.47
5. Step 5: Solve for x
   x = 1,092,300.47/1,328.10
6. Step 6: Final answer
   x = 822.45