Finding the Fourth Proportional to 1,436.88, 2,144.88 and 1,321.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,436.88 : 2,144.88 = 1,321.20 : x
2. Step 2: Convert to fraction form
   1,436.88/2,144.88 = 1,321.20/x
3. Step 3: Cross multiply
   1,436.88x = 2,144.88 × 1,321.20
4. Step 4: Simplify right side
   1,436.88x = 2,833,815.46
5. Step 5: Solve for x
   x = 2,833,815.46/1,436.88
6. Step 6: Final answer
   x = 1,972.20