Finding the Fourth Proportional to 1,381.59, 1,906.87 and 784.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.59 : 1,906.87 = 784.09 : x
2. Step 2: Convert to fraction form
   1,381.59/1,906.87 = 784.09/x
3. Step 3: Cross multiply
   1,381.59x = 1,906.87 × 784.09
4. Step 4: Simplify right side
   1,381.59x = 1,495,157.70
5. Step 5: Solve for x
   x = 1,495,157.70/1,381.59
6. Step 6: Final answer
   x = 1,082.20