Finding the Fourth Proportional to 2,538.59, 3,807.99 and 784.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,538.59 : 3,807.99 = 784.78 : x
2. Step 2: Convert to fraction form
   2,538.59/3,807.99 = 784.78/x
3. Step 3: Cross multiply
   2,538.59x = 3,807.99 × 784.78
4. Step 4: Simplify right side
   2,538.59x = 2,988,424.87
5. Step 5: Solve for x
   x = 2,988,424.87/2,538.59
6. Step 6: Final answer
   x = 1,177.20