Finding the Fourth Proportional to 1,405.56, 1,939.68 and 784.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.56 : 1,939.68 = 784.56 : x
2. Step 2: Convert to fraction form
   1,405.56/1,939.68 = 784.56/x
3. Step 3: Cross multiply
   1,405.56x = 1,939.68 × 784.56
4. Step 4: Simplify right side
   1,405.56x = 1,521,795.34
5. Step 5: Solve for x
   x = 1,521,795.34/1,405.56
6. Step 6: Final answer
   x = 1,082.70