Finding the Fourth Proportional to 1,109.99, 1,665.20 and 379.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.99 : 1,665.20 = 379.69 : x
2. Step 2: Convert to fraction form
   1,109.99/1,665.20 = 379.69/x
3. Step 3: Cross multiply
   1,109.99x = 1,665.20 × 379.69
4. Step 4: Simplify right side
   1,109.99x = 632,256.57
5. Step 5: Solve for x
   x = 632,256.57/1,109.99
6. Step 6: Final answer
   x = 569.60