Finding the Fourth Proportional to 2,051.72, 3,078.72 and 1,231.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,051.72 : 3,078.72 = 1,231.55 : x
2. Step 2: Convert to fraction form
   2,051.72/3,078.72 = 1,231.55/x
3. Step 3: Cross multiply
   2,051.72x = 3,078.72 × 1,231.55
4. Step 4: Simplify right side
   2,051.72x = 3,791,597.62
5. Step 5: Solve for x
   x = 3,791,597.62/2,051.72
6. Step 6: Final answer
   x = 1,848.01