Finding the Fourth Proportional to 78.85, 118.31 and 49.99

Step by Step Solution

1. Step 1: Write the proportion equation
   78.85 : 118.31 = 49.99 : x
2. Step 2: Convert to fraction form
   78.85/118.31 = 49.99/x
3. Step 3: Cross multiply
   78.85x = 118.31 × 49.99
4. Step 4: Simplify right side
   78.85x = 5,914.32
5. Step 5: Solve for x
   x = 5,914.32/78.85
6. Step 6: Final answer
   x = 75.01