Finding the Fourth Proportional to 100.41, 138.56 and 61.59

Step by Step Solution

1. Step 1: Write the proportion equation
   100.41 : 138.56 = 61.59 : x
2. Step 2: Convert to fraction form
   100.41/138.56 = 61.59/x
3. Step 3: Cross multiply
   100.41x = 138.56 × 61.59
4. Step 4: Simplify right side
   100.41x = 8,533.37
5. Step 5: Solve for x
   x = 8,533.37/100.41
6. Step 6: Final answer
   x = 84.99