Finding the Fourth Proportional to 1,169.59, 1,613.98 and 645.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,169.59 : 1,613.98 = 645.61 : x
2. Step 2: Convert to fraction form
   1,169.59/1,613.98 = 645.61/x
3. Step 3: Cross multiply
   1,169.59x = 1,613.98 × 645.61
4. Step 4: Simplify right side
   1,169.59x = 1,042,001.63
5. Step 5: Solve for x
   x = 1,042,001.63/1,169.59
6. Step 6: Final answer
   x = 890.91