Finding the Fourth Proportional to 90.42, 124.86 and 61.38

Step by Step Solution

1. Step 1: Write the proportion equation
   90.42 : 124.86 = 61.38 : x
2. Step 2: Convert to fraction form
   90.42/124.86 = 61.38/x
3. Step 3: Cross multiply
   90.42x = 124.86 × 61.38
4. Step 4: Simplify right side
   90.42x = 7,663.91
5. Step 5: Solve for x
   x = 7,663.91/90.42
6. Step 6: Final answer
   x = 84.76