Finding the Fourth Proportional to 100.53, 150.83 and 42.79

Step by Step Solution

1. Step 1: Write the proportion equation
   100.53 : 150.83 = 42.79 : x
2. Step 2: Convert to fraction form
   100.53/150.83 = 42.79/x
3. Step 3: Cross multiply
   100.53x = 150.83 × 42.79
4. Step 4: Simplify right side
   100.53x = 6,454.02
5. Step 5: Solve for x
   x = 6,454.02/100.53
6. Step 6: Final answer
   x = 64.20