Finding the Fourth Proportional to 1,357.78, 1,873.72 and 768.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,357.78 : 1,873.72 = 768.30 : x
2. Step 2: Convert to fraction form
   1,357.78/1,873.72 = 768.30/x
3. Step 3: Cross multiply
   1,357.78x = 1,873.72 × 768.30
4. Step 4: Simplify right side
   1,357.78x = 1,439,579.08
5. Step 5: Solve for x
   x = 1,439,579.08/1,357.78
6. Step 6: Final answer
   x = 1,060.24