Finding the Fourth Proportional to 91.65, 137.50 and 42.91

Step by Step Solution

1. Step 1: Write the proportion equation
   91.65 : 137.50 = 42.91 : x
2. Step 2: Convert to fraction form
   91.65/137.50 = 42.91/x
3. Step 3: Cross multiply
   91.65x = 137.50 × 42.91
4. Step 4: Simplify right side
   91.65x = 5,899.67
5. Step 5: Solve for x
   x = 5,899.67/91.65
6. Step 6: Final answer
   x = 64.37