Finding the Fourth Proportional to 1,417.69, 2,128.56 and 868.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,417.69 : 2,128.56 = 868.21 : x
2. Step 2: Convert to fraction form
   1,417.69/2,128.56 = 868.21/x
3. Step 3: Cross multiply
   1,417.69x = 2,128.56 × 868.21
4. Step 4: Simplify right side
   1,417.69x = 1,848,037.08
5. Step 5: Solve for x
   x = 1,848,037.08/1,417.69
6. Step 6: Final answer
   x = 1,303.56