Finding the Fourth Proportional to 86.87, 130.17 and 56.34

Step by Step Solution

1. Step 1: Write the proportion equation
   86.87 : 130.17 = 56.34 : x
2. Step 2: Convert to fraction form
   86.87/130.17 = 56.34/x
3. Step 3: Cross multiply
   86.87x = 130.17 × 56.34
4. Step 4: Simplify right side
   86.87x = 7,333.78
5. Step 5: Solve for x
   x = 7,333.78/86.87
6. Step 6: Final answer
   x = 84.42