Finding the Fourth Proportional to 71.32, 98.38 and 42.18

Step by Step Solution

1. Step 1: Write the proportion equation
   71.32 : 98.38 = 42.18 : x
2. Step 2: Convert to fraction form
   71.32/98.38 = 42.18/x
3. Step 3: Cross multiply
   71.32x = 98.38 × 42.18
4. Step 4: Simplify right side
   71.32x = 4,149.67
5. Step 5: Solve for x
   x = 4,149.67/71.32
6. Step 6: Final answer
   x = 58.18