Finding the Fourth Proportional to 1,780.28, 2,456.76 and 994.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,780.28 : 2,456.76 = 994.40 : x
2. Step 2: Convert to fraction form
   1,780.28/2,456.76 = 994.40/x
3. Step 3: Cross multiply
   1,780.28x = 2,456.76 × 994.40
4. Step 4: Simplify right side
   1,780.28x = 2,443,002.14
5. Step 5: Solve for x
   x = 2,443,002.14/1,780.28
6. Step 6: Final answer
   x = 1,372.26