Finding the Fourth Proportional to 78.59, 117.65 and 65.00

Step by Step Solution

1. Step 1: Write the proportion equation
   78.59 : 117.65 = 65.00 : x
2. Step 2: Convert to fraction form
   78.59/117.65 = 65.00/x
3. Step 3: Cross multiply
   78.59x = 117.65 × 65.00
4. Step 4: Simplify right side
   78.59x = 7,646.82
5. Step 5: Solve for x
   x = 7,646.82/78.59
6. Step 6: Final answer
   x = 97.31