Finding the Fourth Proportional to 1,061.94, 1,590.48 and 645.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.94 : 1,590.48 = 645.60 : x
2. Step 2: Convert to fraction form
   1,061.94/1,590.48 = 645.60/x
3. Step 3: Cross multiply
   1,061.94x = 1,590.48 × 645.60
4. Step 4: Simplify right side
   1,061.94x = 1,026,813.89
5. Step 5: Solve for x
   x = 1,026,813.89/1,061.94
6. Step 6: Final answer
   x = 966.92