Finding the Fourth Proportional to 1,169.48, 1,613.88 and 645.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,169.48 : 1,613.88 = 645.50 : x
2. Step 2: Convert to fraction form
   1,169.48/1,613.88 = 645.50/x
3. Step 3: Cross multiply
   1,169.48x = 1,613.88 × 645.50
4. Step 4: Simplify right side
   1,169.48x = 1,041,759.54
5. Step 5: Solve for x
   x = 1,041,759.54/1,169.48
6. Step 6: Final answer
   x = 890.79