Finding the Fourth Proportional to 90.49, 124.72 and 70.78

Step by Step Solution

1. Step 1: Write the proportion equation
   90.49 : 124.72 = 70.78 : x
2. Step 2: Convert to fraction form
   90.49/124.72 = 70.78/x
3. Step 3: Cross multiply
   90.49x = 124.72 × 70.78
4. Step 4: Simplify right side
   90.49x = 8,827.86
5. Step 5: Solve for x
   x = 8,827.86/90.49
6. Step 6: Final answer
   x = 97.56