Finding the Fourth Proportional to 111.45, 153.78 and 69.99

Step by Step Solution

1. Step 1: Write the proportion equation
   111.45 : 153.78 = 69.99 : x
2. Step 2: Convert to fraction form
   111.45/153.78 = 69.99/x
3. Step 3: Cross multiply
   111.45x = 153.78 × 69.99
4. Step 4: Simplify right side
   111.45x = 10,762.29
5. Step 5: Solve for x
   x = 10,762.29/111.45
6. Step 6: Final answer
   x = 96.57