Finding the Fourth Proportional to 73.12, 100.90 and 42.02

Step by Step Solution

1. Step 1: Write the proportion equation
   73.12 : 100.90 = 42.02 : x
2. Step 2: Convert to fraction form
   73.12/100.90 = 42.02/x
3. Step 3: Cross multiply
   73.12x = 100.90 × 42.02
4. Step 4: Simplify right side
   73.12x = 4,239.93
5. Step 5: Solve for x
   x = 4,239.93/73.12
6. Step 6: Final answer
   x = 57.99