Finding the Fourth Proportional to 1,113.33, 1,536.43 and 641.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,113.33 : 1,536.43 = 641.31 : x
2. Step 2: Convert to fraction form
   1,113.33/1,536.43 = 641.31/x
3. Step 3: Cross multiply
   1,113.33x = 1,536.43 × 641.31
4. Step 4: Simplify right side
   1,113.33x = 985,327.92
5. Step 5: Solve for x
   x = 985,327.92/1,113.33
6. Step 6: Final answer
   x = 885.03