Finding the Fourth Proportional to 1,072.16, 1,608.72 and 379.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,072.16 : 1,608.72 = 379.34 : x
2. Step 2: Convert to fraction form
   1,072.16/1,608.72 = 379.34/x
3. Step 3: Cross multiply
   1,072.16x = 1,608.72 × 379.34
4. Step 4: Simplify right side
   1,072.16x = 610,243.80
5. Step 5: Solve for x
   x = 610,243.80/1,072.16
6. Step 6: Final answer
   x = 569.17