Finding the Fourth Proportional to 1,169.37, 1,613.79 and 645.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,169.37 : 1,613.79 = 645.57 : x
2. Step 2: Convert to fraction form
   1,169.37/1,613.79 = 645.57/x
3. Step 3: Cross multiply
   1,169.37x = 1,613.79 × 645.57
4. Step 4: Simplify right side
   1,169.37x = 1,041,814.41
5. Step 5: Solve for x
   x = 1,041,814.41/1,169.37
6. Step 6: Final answer
   x = 890.92