Finding the Fourth Proportional to 89.42, 123.35 and 61.40

Step by Step Solution

1. Step 1: Write the proportion equation
   89.42 : 123.35 = 61.40 : x
2. Step 2: Convert to fraction form
   89.42/123.35 = 61.40/x
3. Step 3: Cross multiply
   89.42x = 123.35 × 61.40
4. Step 4: Simplify right side
   89.42x = 7,572.77
5. Step 5: Solve for x
   x = 7,572.77/89.42
6. Step 6: Final answer
   x = 84.69