Finding the Fourth Proportional to 1,176.69, 1,623.81 and 645.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,176.69 : 1,623.81 = 645.59 : x
2. Step 2: Convert to fraction form
   1,176.69/1,623.81 = 645.59/x
3. Step 3: Cross multiply
   1,176.69x = 1,623.81 × 645.59
4. Step 4: Simplify right side
   1,176.69x = 1,048,307.38
5. Step 5: Solve for x
   x = 1,048,307.38/1,176.69
6. Step 6: Final answer
   x = 890.90