Finding the Fourth Proportional to 78.50, 117.59 and 47.99

Step by Step Solution

1. Step 1: Write the proportion equation
   78.50 : 117.59 = 47.99 : x
2. Step 2: Convert to fraction form
   78.50/117.59 = 47.99/x
3. Step 3: Cross multiply
   78.50x = 117.59 × 47.99
4. Step 4: Simplify right side
   78.50x = 5,643.20
5. Step 5: Solve for x
   x = 5,643.20/78.50
6. Step 6: Final answer
   x = 71.89