Finding the Fourth Proportional to 111.81, 167.74 and 42.40

Step by Step Solution

1. Step 1: Write the proportion equation
   111.81 : 167.74 = 42.40 : x
2. Step 2: Convert to fraction form
   111.81/167.74 = 42.40/x
3. Step 3: Cross multiply
   111.81x = 167.74 × 42.40
4. Step 4: Simplify right side
   111.81x = 7,111.81
5. Step 5: Solve for x
   x = 7,111.81/111.81
6. Step 6: Final answer
   x = 63.60