Finding the Fourth Proportional to 89.90, 123.74 and 63.98

Step by Step Solution

1. Step 1: Write the proportion equation
   89.90 : 123.74 = 63.98 : x
2. Step 2: Convert to fraction form
   89.90/123.74 = 63.98/x
3. Step 3: Cross multiply
   89.90x = 123.74 × 63.98
4. Step 4: Simplify right side
   89.90x = 7,916.89
5. Step 5: Solve for x
   x = 7,916.89/89.90
6. Step 6: Final answer
   x = 88.06