Finding the Fourth Proportional to 1,405.61, 1,939.74 and 784.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.61 : 1,939.74 = 784.61 : x
2. Step 2: Convert to fraction form
   1,405.61/1,939.74 = 784.61/x
3. Step 3: Cross multiply
   1,405.61x = 1,939.74 × 784.61
4. Step 4: Simplify right side
   1,405.61x = 1,521,939.40
5. Step 5: Solve for x
   x = 1,521,939.40/1,405.61
6. Step 6: Final answer
   x = 1,082.76