Finding the Fourth Proportional to 1,426.78, 1,967.15 and 1,213.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,426.78 : 1,967.15 = 1,213.88 : x
2. Step 2: Convert to fraction form
   1,426.78/1,967.15 = 1,213.88/x
3. Step 3: Cross multiply
   1,426.78x = 1,967.15 × 1,213.88
4. Step 4: Simplify right side
   1,426.78x = 2,387,884.04
5. Step 5: Solve for x
   x = 2,387,884.04/1,426.78
6. Step 6: Final answer
   x = 1,673.62