Finding the Fourth Proportional to 1,110.89, 1,532.83 and 638.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,110.89 : 1,532.83 = 638.67 : x
2. Step 2: Convert to fraction form
   1,110.89/1,532.83 = 638.67/x
3. Step 3: Cross multiply
   1,110.89x = 1,532.83 × 638.67
4. Step 4: Simplify right side
   1,110.89x = 978,972.54
5. Step 5: Solve for x
   x = 978,972.54/1,110.89
6. Step 6: Final answer
   x = 881.25