Finding the Fourth Proportional to 1,308.61, 1,805.78 and 784.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.61 : 1,805.78 = 784.54 : x
2. Step 2: Convert to fraction form
   1,308.61/1,805.78 = 784.54/x
3. Step 3: Cross multiply
   1,308.61x = 1,805.78 × 784.54
4. Step 4: Simplify right side
   1,308.61x = 1,416,693.69
5. Step 5: Solve for x
   x = 1,416,693.69/1,308.61
6. Step 6: Final answer
   x = 1,082.60