Finding the Fourth Proportional to 99.98, 137.98 and 61.17

Step by Step Solution

1. Step 1: Write the proportion equation
   99.98 : 137.98 = 61.17 : x
2. Step 2: Convert to fraction form
   99.98/137.98 = 61.17/x
3. Step 3: Cross multiply
   99.98x = 137.98 × 61.17
4. Step 4: Simplify right side
   99.98x = 8,440.49
5. Step 5: Solve for x
   x = 8,440.49/99.98
6. Step 6: Final answer
   x = 84.42