Finding the Fourth Proportional to 89.49, 123.50 and 56.74

Step by Step Solution

1. Step 1: Write the proportion equation
   89.49 : 123.50 = 56.74 : x
2. Step 2: Convert to fraction form
   89.49/123.50 = 56.74/x
3. Step 3: Cross multiply
   89.49x = 123.50 × 56.74
4. Step 4: Simplify right side
   89.49x = 7,006.80
5. Step 5: Solve for x
   x = 7,006.80/89.49
6. Step 6: Final answer
   x = 78.30