Finding the Fourth Proportional to 86.98, 119.86 and 65.10

Step by Step Solution

1. Step 1: Write the proportion equation
   86.98 : 119.86 = 65.10 : x
2. Step 2: Convert to fraction form
   86.98/119.86 = 65.10/x
3. Step 3: Cross multiply
   86.98x = 119.86 × 65.10
4. Step 4: Simplify right side
   86.98x = 7,802.89
5. Step 5: Solve for x
   x = 7,802.89/86.98
6. Step 6: Final answer
   x = 89.71