Finding the Third Proportional to 1,216.90 and 1,721.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,216.90 : 1,721.88 = 1,721.88 : x
2. Step 2: Convert to fraction form
   1,216.90/1,721.88 = 1,721.88/x
3. Step 3: Cross multiply
   1,216.90x = 1,721.88 × 1,721.88
4. Step 4: Simplify right side
   1,216.90x = 2,964,880.42
5. Step 5: Solve for x
   x = 2,964,880.42/1,216.90
6. Step 6: Final answer
   x = 2,436.42