Finding the Fourth Proportional to 1,278.72, 1,913.76 and 792.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,278.72 : 1,913.76 = 792.18 : x
2. Step 2: Convert to fraction form
   1,278.72/1,913.76 = 792.18/x
3. Step 3: Cross multiply
   1,278.72x = 1,913.76 × 792.18
4. Step 4: Simplify right side
   1,278.72x = 1,516,042.40
5. Step 5: Solve for x
   x = 1,516,042.40/1,278.72
6. Step 6: Final answer
   x = 1,185.59