Finding the Fourth Proportional to 113.57, 156.71 and 64.43

Step by Step Solution

1. Step 1: Write the proportion equation
   113.57 : 156.71 = 64.43 : x
2. Step 2: Convert to fraction form
   113.57/156.71 = 64.43/x
3. Step 3: Cross multiply
   113.57x = 156.71 × 64.43
4. Step 4: Simplify right side
   113.57x = 10,096.89
5. Step 5: Solve for x
   x = 10,096.89/113.57
6. Step 6: Final answer
   x = 88.91