Finding the Fourth Proportional to 1,105.89, 1,525.79 and 663.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.89 : 1,525.79 = 663.63 : x
2. Step 2: Convert to fraction form
   1,105.89/1,525.79 = 663.63/x
3. Step 3: Cross multiply
   1,105.89x = 1,525.79 × 663.63
4. Step 4: Simplify right side
   1,105.89x = 1,012,560.02
5. Step 5: Solve for x
   x = 1,012,560.02/1,105.89
6. Step 6: Final answer
   x = 915.61