Finding the Fourth Proportional to 1,054.82, 1,581.73 and 644.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,054.82 : 1,581.73 = 644.15 : x
2. Step 2: Convert to fraction form
   1,054.82/1,581.73 = 644.15/x
3. Step 3: Cross multiply
   1,054.82x = 1,581.73 × 644.15
4. Step 4: Simplify right side
   1,054.82x = 1,018,873.72
5. Step 5: Solve for x
   x = 1,018,873.72/1,054.82
6. Step 6: Final answer
   x = 965.92