Finding the Fourth Proportional to 111.32, 153.57 and 64.69

Step by Step Solution

1. Step 1: Write the proportion equation
   111.32 : 153.57 = 64.69 : x
2. Step 2: Convert to fraction form
   111.32/153.57 = 64.69/x
3. Step 3: Cross multiply
   111.32x = 153.57 × 64.69
4. Step 4: Simplify right side
   111.32x = 9,934.30
5. Step 5: Solve for x
   x = 9,934.30/111.32
6. Step 6: Final answer
   x = 89.24