Finding the Fourth Proportional to 1,351.72, 1,866.09 and 880.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,351.72 : 1,866.09 = 880.30 : x
2. Step 2: Convert to fraction form
   1,351.72/1,866.09 = 880.30/x
3. Step 3: Cross multiply
   1,351.72x = 1,866.09 × 880.30
4. Step 4: Simplify right side
   1,351.72x = 1,642,719.03
5. Step 5: Solve for x
   x = 1,642,719.03/1,351.72
6. Step 6: Final answer
   x = 1,215.28