Finding the Fourth Proportional to 2,631.91, 3,947.80 and 783.03

Step by Step Solution

1. Step 1: Write the proportion equation
   2,631.91 : 3,947.80 = 783.03 : x
2. Step 2: Convert to fraction form
   2,631.91/3,947.80 = 783.03/x
3. Step 3: Cross multiply
   2,631.91x = 3,947.80 × 783.03
4. Step 4: Simplify right side
   2,631.91x = 3,091,245.83
5. Step 5: Solve for x
   x = 3,091,245.83/2,631.91
6. Step 6: Final answer
   x = 1,174.53