Finding the Fourth Proportional to 71.68, 98.91 and 42.17

Step by Step Solution

1. Step 1: Write the proportion equation
   71.68 : 98.91 = 42.17 : x
2. Step 2: Convert to fraction form
   71.68/98.91 = 42.17/x
3. Step 3: Cross multiply
   71.68x = 98.91 × 42.17
4. Step 4: Simplify right side
   71.68x = 4,171.03
5. Step 5: Solve for x
   x = 4,171.03/71.68
6. Step 6: Final answer
   x = 58.19