Finding the Fourth Proportional to 1,092.50, 1,638.78 and 270.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,092.50 : 1,638.78 = 270.78 : x
2. Step 2: Convert to fraction form
   1,092.50/1,638.78 = 270.78/x
3. Step 3: Cross multiply
   1,092.50x = 1,638.78 × 270.78
4. Step 4: Simplify right side
   1,092.50x = 443,748.85
5. Step 5: Solve for x
   x = 443,748.85/1,092.50
6. Step 6: Final answer
   x = 406.18