Finding the Fourth Proportional to 78.96, 118.38 and 42.84

Step by Step Solution

1. Step 1: Write the proportion equation
   78.96 : 118.38 = 42.84 : x
2. Step 2: Convert to fraction form
   78.96/118.38 = 42.84/x
3. Step 3: Cross multiply
   78.96x = 118.38 × 42.84
4. Step 4: Simplify right side
   78.96x = 5,071.40
5. Step 5: Solve for x
   x = 5,071.40/78.96
6. Step 6: Final answer
   x = 64.23