Finding the Fourth Proportional to 1,493.30, 2,238.51 and 518.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,493.30 : 2,238.51 = 518.78 : x
2. Step 2: Convert to fraction form
   1,493.30/2,238.51 = 518.78/x
3. Step 3: Cross multiply
   1,493.30x = 2,238.51 × 518.78
4. Step 4: Simplify right side
   1,493.30x = 1,161,301.76
5. Step 5: Solve for x
   x = 1,161,301.76/1,493.30
6. Step 6: Final answer
   x = 777.67