Finding the Fourth Proportional to 1,978.74, 2,727.81 and 1,387.44

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.74 : 2,727.81 = 1,387.44 : x
2. Step 2: Convert to fraction form
   1,978.74/2,727.81 = 1,387.44/x
3. Step 3: Cross multiply
   1,978.74x = 2,727.81 × 1,387.44
4. Step 4: Simplify right side
   1,978.74x = 3,784,672.71
5. Step 5: Solve for x
   x = 3,784,672.71/1,978.74
6. Step 6: Final answer
   x = 1,912.67