Finding the Fourth Proportional to 91.64, 137.34 and 42.88

Step by Step Solution

1. Step 1: Write the proportion equation
   91.64 : 137.34 = 42.88 : x
2. Step 2: Convert to fraction form
   91.64/137.34 = 42.88/x
3. Step 3: Cross multiply
   91.64x = 137.34 × 42.88
4. Step 4: Simplify right side
   91.64x = 5,889.14
5. Step 5: Solve for x
   x = 5,889.14/91.64
6. Step 6: Final answer
   x = 64.26