Finding the Fourth Proportional to 2,081.20, 3,123.24 and 783.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,081.20 : 3,123.24 = 783.76 : x
2. Step 2: Convert to fraction form
   2,081.20/3,123.24 = 783.76/x
3. Step 3: Cross multiply
   2,081.20x = 3,123.24 × 783.76
4. Step 4: Simplify right side
   2,081.20x = 2,447,870.58
5. Step 5: Solve for x
   x = 2,447,870.58/2,081.20
6. Step 6: Final answer
   x = 1,176.18