Finding the Fourth Proportional to 89.61, 123.63 and 71.18

Step by Step Solution

1. Step 1: Write the proportion equation
   89.61 : 123.63 = 71.18 : x
2. Step 2: Convert to fraction form
   89.61/123.63 = 71.18/x
3. Step 3: Cross multiply
   89.61x = 123.63 × 71.18
4. Step 4: Simplify right side
   89.61x = 8,799.56
5. Step 5: Solve for x
   x = 8,799.56/89.61
6. Step 6: Final answer
   x = 98.20