Finding the Fourth Proportional to 1,308.55, 1,805.57 and 784.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.55 : 1,805.57 = 784.60 : x
2. Step 2: Convert to fraction form
   1,308.55/1,805.57 = 784.60/x
3. Step 3: Cross multiply
   1,308.55x = 1,805.57 × 784.60
4. Step 4: Simplify right side
   1,308.55x = 1,416,650.22
5. Step 5: Solve for x
   x = 1,416,650.22/1,308.55
6. Step 6: Final answer
   x = 1,082.61