Finding the Fourth Proportional to 72.90, 108.72 and 65.19

Step by Step Solution

1. Step 1: Write the proportion equation
   72.90 : 108.72 = 65.19 : x
2. Step 2: Convert to fraction form
   72.90/108.72 = 65.19/x
3. Step 3: Cross multiply
   72.90x = 108.72 × 65.19
4. Step 4: Simplify right side
   72.90x = 7,087.46
5. Step 5: Solve for x
   x = 7,087.46/72.90
6. Step 6: Final answer
   x = 97.22