Finding the Fourth Proportional to 100.91, 139.27 and 57.24

Step by Step Solution

1. Step 1: Write the proportion equation
   100.91 : 139.27 = 57.24 : x
2. Step 2: Convert to fraction form
   100.91/139.27 = 57.24/x
3. Step 3: Cross multiply
   100.91x = 139.27 × 57.24
4. Step 4: Simplify right side
   100.91x = 7,971.67
5. Step 5: Solve for x
   x = 7,971.67/100.91
6. Step 6: Final answer
   x = 79.00