Finding the Fourth Proportional to 89.91, 123.93 and 57.14

Step by Step Solution

1. Step 1: Write the proportion equation
   89.91 : 123.93 = 57.14 : x
2. Step 2: Convert to fraction form
   89.91/123.93 = 57.14/x
3. Step 3: Cross multiply
   89.91x = 123.93 × 57.14
4. Step 4: Simplify right side
   89.91x = 7,081.21
5. Step 5: Solve for x
   x = 7,081.21/89.91
6. Step 6: Final answer
   x = 78.76