Finding the Fourth Proportional to 1,105.86, 1,525.68 and 663.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.86 : 1,525.68 = 663.60 : x
2. Step 2: Convert to fraction form
   1,105.86/1,525.68 = 663.60/x
3. Step 3: Cross multiply
   1,105.86x = 1,525.68 × 663.60
4. Step 4: Simplify right side
   1,105.86x = 1,012,441.25
5. Step 5: Solve for x
   x = 1,012,441.25/1,105.86
6. Step 6: Final answer
   x = 915.52