Finding the Fourth Proportional to 89.49, 123.46 and 56.76

Step by Step Solution

1. Step 1: Write the proportion equation
   89.49 : 123.46 = 56.76 : x
2. Step 2: Convert to fraction form
   89.49/123.46 = 56.76/x
3. Step 3: Cross multiply
   89.49x = 123.46 × 56.76
4. Step 4: Simplify right side
   89.49x = 7,006.98
5. Step 5: Solve for x
   x = 7,006.98/89.49
6. Step 6: Final answer
   x = 78.30