Finding the Fourth Proportional to 86.34, 129.42 and 43.50

Step by Step Solution

1. Step 1: Write the proportion equation
   86.34 : 129.42 = 43.50 : x
2. Step 2: Convert to fraction form
   86.34/129.42 = 43.50/x
3. Step 3: Cross multiply
   86.34x = 129.42 × 43.50
4. Step 4: Simplify right side
   86.34x = 5,629.77
5. Step 5: Solve for x
   x = 5,629.77/86.34
6. Step 6: Final answer
   x = 65.20