Finding the Fourth Proportional to 99.79, 149.61 and 42.83

Step by Step Solution

1. Step 1: Write the proportion equation
   99.79 : 149.61 = 42.83 : x
2. Step 2: Convert to fraction form
   99.79/149.61 = 42.83/x
3. Step 3: Cross multiply
   99.79x = 149.61 × 42.83
4. Step 4: Simplify right side
   99.79x = 6,407.58
5. Step 5: Solve for x
   x = 6,407.58/99.79
6. Step 6: Final answer
   x = 64.21