Finding the Fourth Proportional to 1,053.24, 1,577.50 and 642.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,053.24 : 1,577.50 = 642.04 : x
2. Step 2: Convert to fraction form
   1,053.24/1,577.50 = 642.04/x
3. Step 3: Cross multiply
   1,053.24x = 1,577.50 × 642.04
4. Step 4: Simplify right side
   1,053.24x = 1,012,818.10
5. Step 5: Solve for x
   x = 1,012,818.10/1,053.24
6. Step 6: Final answer
   x = 961.62