Finding the Fourth Proportional to 1,061.35, 1,464.92 and 641.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.35 : 1,464.92 = 641.72 : x
2. Step 2: Convert to fraction form
   1,061.35/1,464.92 = 641.72/x
3. Step 3: Cross multiply
   1,061.35x = 1,464.92 × 641.72
4. Step 4: Simplify right side
   1,061.35x = 940,068.46
5. Step 5: Solve for x
   x = 940,068.46/1,061.35
6. Step 6: Final answer
   x = 885.73