Finding the Fourth Proportional to 78.32, 117.50 and 42.23

Step by Step Solution

1. Step 1: Write the proportion equation
   78.32 : 117.50 = 42.23 : x
2. Step 2: Convert to fraction form
   78.32/117.50 = 42.23/x
3. Step 3: Cross multiply
   78.32x = 117.50 × 42.23
4. Step 4: Simplify right side
   78.32x = 4,962.03
5. Step 5: Solve for x
   x = 4,962.03/78.32
6. Step 6: Final answer
   x = 63.36