Finding the Fourth Proportional to 900.27, 1,239.89 and 775.89

Step by Step Solution

1. Step 1: Write the proportion equation
   900.27 : 1,239.89 = 775.89 : x
2. Step 2: Convert to fraction form
   900.27/1,239.89 = 775.89/x
3. Step 3: Cross multiply
   900.27x = 1,239.89 × 775.89
4. Step 4: Simplify right side
   900.27x = 962,014.37
5. Step 5: Solve for x
   x = 962,014.37/900.27
6. Step 6: Final answer
   x = 1,068.58