Finding the Fourth Proportional to 1,172.56, 1,618.18 and 648.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,172.56 : 1,618.18 = 648.69 : x
2. Step 2: Convert to fraction form
   1,172.56/1,618.18 = 648.69/x
3. Step 3: Cross multiply
   1,172.56x = 1,618.18 × 648.69
4. Step 4: Simplify right side
   1,172.56x = 1,049,693.94
5. Step 5: Solve for x
   x = 1,049,693.94/1,172.56
6. Step 6: Final answer
   x = 895.22