Finding the Fourth Proportional to 1,428.17, 1,970.33 and 868.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,428.17 : 1,970.33 = 868.25 : x
2. Step 2: Convert to fraction form
   1,428.17/1,970.33 = 868.25/x
3. Step 3: Cross multiply
   1,428.17x = 1,970.33 × 868.25
4. Step 4: Simplify right side
   1,428.17x = 1,710,739.61
5. Step 5: Solve for x
   x = 1,710,739.61/1,428.17
6. Step 6: Final answer
   x = 1,197.86