Finding the Fourth Proportional to 1,192.56, 1,643.29 and 912.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,192.56 : 1,643.29 = 912.79 : x
2. Step 2: Convert to fraction form
   1,192.56/1,643.29 = 912.79/x
3. Step 3: Cross multiply
   1,192.56x = 1,643.29 × 912.79
4. Step 4: Simplify right side
   1,192.56x = 1,499,978.68
5. Step 5: Solve for x
   x = 1,499,978.68/1,192.56
6. Step 6: Final answer
   x = 1,257.78