Finding the Fourth Proportional to 73.09, 100.78 and 57.50

Step by Step Solution

1. Step 1: Write the proportion equation
   73.09 : 100.78 = 57.50 : x
2. Step 2: Convert to fraction form
   73.09/100.78 = 57.50/x
3. Step 3: Cross multiply
   73.09x = 100.78 × 57.50
4. Step 4: Simplify right side
   73.09x = 5,794.06
5. Step 5: Solve for x
   x = 5,794.06/73.09
6. Step 6: Final answer
   x = 79.28