Finding the Fourth Proportional to 78.34, 117.56 and 42.22

Step by Step Solution

1. Step 1: Write the proportion equation
   78.34 : 117.56 = 42.22 : x
2. Step 2: Convert to fraction form
   78.34/117.56 = 42.22/x
3. Step 3: Cross multiply
   78.34x = 117.56 × 42.22
4. Step 4: Simplify right side
   78.34x = 4,963.38
5. Step 5: Solve for x
   x = 4,963.38/78.34
6. Step 6: Final answer
   x = 63.36