Finding the Fourth Proportional to 1,109.76, 1,664.34 and 379.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.76 : 1,664.34 = 379.50 : x
2. Step 2: Convert to fraction form
   1,109.76/1,664.34 = 379.50/x
3. Step 3: Cross multiply
   1,109.76x = 1,664.34 × 379.50
4. Step 4: Simplify right side
   1,109.76x = 631,617.03
5. Step 5: Solve for x
   x = 631,617.03/1,109.76
6. Step 6: Final answer
   x = 569.15