Finding the Fourth Proportional to 1,187.46, 1,638.72 and 663.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,187.46 : 1,638.72 = 663.52 : x
2. Step 2: Convert to fraction form
   1,187.46/1,638.72 = 663.52/x
3. Step 3: Cross multiply
   1,187.46x = 1,638.72 × 663.52
4. Step 4: Simplify right side
   1,187.46x = 1,087,323.49
5. Step 5: Solve for x
   x = 1,087,323.49/1,187.46
6. Step 6: Final answer
   x = 915.67