Finding the Fourth Proportional to 99.88, 149.82 and 42.88

Step by Step Solution

1. Step 1: Write the proportion equation
   99.88 : 149.82 = 42.88 : x
2. Step 2: Convert to fraction form
   99.88/149.82 = 42.88/x
3. Step 3: Cross multiply
   99.88x = 149.82 × 42.88
4. Step 4: Simplify right side
   99.88x = 6,423.32
5. Step 5: Solve for x
   x = 6,423.32/99.88
6. Step 6: Final answer
   x = 64.31