Finding the Fourth Proportional to 1,111.52, 1,665.46 and 380.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.52 : 1,665.46 = 380.70 : x
2. Step 2: Convert to fraction form
   1,111.52/1,665.46 = 380.70/x
3. Step 3: Cross multiply
   1,111.52x = 1,665.46 × 380.70
4. Step 4: Simplify right side
   1,111.52x = 634,039.67
5. Step 5: Solve for x
   x = 634,039.67/1,111.52
6. Step 6: Final answer
   x = 570.42