Finding the Fourth Proportional to 1,111.29, 1,667.12 and 380.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.29 : 1,667.12 = 380.70 : x
2. Step 2: Convert to fraction form
   1,111.29/1,667.12 = 380.70/x
3. Step 3: Cross multiply
   1,111.29x = 1,667.12 × 380.70
4. Step 4: Simplify right side
   1,111.29x = 634,670.68
5. Step 5: Solve for x
   x = 634,670.68/1,111.29
6. Step 6: Final answer
   x = 571.11