Finding the Fourth Proportional to 1,380.96, 2,072.34 and 1,269.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.96 : 2,072.34 = 1,269.72 : x
2. Step 2: Convert to fraction form
   1,380.96/2,072.34 = 1,269.72/x
3. Step 3: Cross multiply
   1,380.96x = 2,072.34 × 1,269.72
4. Step 4: Simplify right side
   1,380.96x = 2,631,291.54
5. Step 5: Solve for x
   x = 2,631,291.54/1,380.96
6. Step 6: Final answer
   x = 1,905.41