Finding the Fourth Proportional to 111.52, 153.86 and 64.86

Step by Step Solution

1. Step 1: Write the proportion equation
   111.52 : 153.86 = 64.86 : x
2. Step 2: Convert to fraction form
   111.52/153.86 = 64.86/x
3. Step 3: Cross multiply
   111.52x = 153.86 × 64.86
4. Step 4: Simplify right side
   111.52x = 9,980.03
5. Step 5: Solve for x
   x = 9,980.03/111.52
6. Step 6: Final answer
   x = 89.49