Finding the Fourth Proportional to 1,282.72, 1,770.28 and 785.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,282.72 : 1,770.28 = 785.69 : x
2. Step 2: Convert to fraction form
   1,282.72/1,770.28 = 785.69/x
3. Step 3: Cross multiply
   1,282.72x = 1,770.28 × 785.69
4. Step 4: Simplify right side
   1,282.72x = 1,390,880.48
5. Step 5: Solve for x
   x = 1,390,880.48/1,282.72
6. Step 6: Final answer
   x = 1,084.32