Finding the Fourth Proportional to 78.71, 117.91 and 59.47

Step by Step Solution

1. Step 1: Write the proportion equation
   78.71 : 117.91 = 59.47 : x
2. Step 2: Convert to fraction form
   78.71/117.91 = 59.47/x
3. Step 3: Cross multiply
   78.71x = 117.91 × 59.47
4. Step 4: Simplify right side
   78.71x = 7,012.11
5. Step 5: Solve for x
   x = 7,012.11/78.71
6. Step 6: Final answer
   x = 89.09