Finding the Fourth Proportional to 1,807.72, 2,709.98 and 781.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,807.72 : 2,709.98 = 781.16 : x
2. Step 2: Convert to fraction form
   1,807.72/2,709.98 = 781.16/x
3. Step 3: Cross multiply
   1,807.72x = 2,709.98 × 781.16
4. Step 4: Simplify right side
   1,807.72x = 2,116,927.98
5. Step 5: Solve for x
   x = 2,116,927.98/1,807.72
6. Step 6: Final answer
   x = 1,171.05