Finding the Fourth Proportional to 1,141.04, 1,574.56 and 643.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,141.04 : 1,574.56 = 643.72 : x
2. Step 2: Convert to fraction form
   1,141.04/1,574.56 = 643.72/x
3. Step 3: Cross multiply
   1,141.04x = 1,574.56 × 643.72
4. Step 4: Simplify right side
   1,141.04x = 1,013,581.82
5. Step 5: Solve for x
   x = 1,013,581.82/1,141.04
6. Step 6: Final answer
   x = 888.30