Finding the Fourth Proportional to 1,282.38, 1,769.31 and 784.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,282.38 : 1,769.31 = 784.50 : x
2. Step 2: Convert to fraction form
   1,282.38/1,769.31 = 784.50/x
3. Step 3: Cross multiply
   1,282.38x = 1,769.31 × 784.50
4. Step 4: Simplify right side
   1,282.38x = 1,388,023.70
5. Step 5: Solve for x
   x = 1,388,023.70/1,282.38
6. Step 6: Final answer
   x = 1,082.38