Finding the Fourth Proportional to 1,222.91, 1,835.35 and 638.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.91 : 1,835.35 = 638.09 : x
2. Step 2: Convert to fraction form
   1,222.91/1,835.35 = 638.09/x
3. Step 3: Cross multiply
   1,222.91x = 1,835.35 × 638.09
4. Step 4: Simplify right side
   1,222.91x = 1,171,118.48
5. Step 5: Solve for x
   x = 1,171,118.48/1,222.91
6. Step 6: Final answer
   x = 957.65