Finding the Fourth Proportional to 1,111.99, 1,666.75 and 380.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.99 : 1,666.75 = 380.56 : x
2. Step 2: Convert to fraction form
   1,111.99/1,666.75 = 380.56/x
3. Step 3: Cross multiply
   1,111.99x = 1,666.75 × 380.56
4. Step 4: Simplify right side
   1,111.99x = 634,298.38
5. Step 5: Solve for x
   x = 634,298.38/1,111.99
6. Step 6: Final answer
   x = 570.42