Finding the Fourth Proportional to 1,219.89, 1,830.12 and 354.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,219.89 : 1,830.12 = 354.18 : x
2. Step 2: Convert to fraction form
   1,219.89/1,830.12 = 354.18/x
3. Step 3: Cross multiply
   1,219.89x = 1,830.12 × 354.18
4. Step 4: Simplify right side
   1,219.89x = 648,191.90
5. Step 5: Solve for x
   x = 648,191.90/1,219.89
6. Step 6: Final answer
   x = 531.35