Finding the Fourth Proportional to 1,111.18, 1,666.96 and 380.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.18 : 1,666.96 = 380.58 : x
2. Step 2: Convert to fraction form
   1,111.18/1,666.96 = 380.58/x
3. Step 3: Cross multiply
   1,111.18x = 1,666.96 × 380.58
4. Step 4: Simplify right side
   1,111.18x = 634,411.64
5. Step 5: Solve for x
   x = 634,411.64/1,111.18
6. Step 6: Final answer
   x = 570.94