Finding the Fourth Proportional to 1,282.25, 1,769.69 and 784.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,282.25 : 1,769.69 = 784.80 : x
2. Step 2: Convert to fraction form
   1,282.25/1,769.69 = 784.80/x
3. Step 3: Cross multiply
   1,282.25x = 1,769.69 × 784.80
4. Step 4: Simplify right side
   1,282.25x = 1,388,848.79
5. Step 5: Solve for x
   x = 1,388,848.79/1,282.25
6. Step 6: Final answer
   x = 1,083.14