Finding the Fourth Proportional to 42.99, 59.28 and 31.37

Step by Step Solution

1. Step 1: Write the proportion equation
   42.99 : 59.28 = 31.37 : x
2. Step 2: Convert to fraction form
   42.99/59.28 = 31.37/x
3. Step 3: Cross multiply
   42.99x = 59.28 × 31.37
4. Step 4: Simplify right side
   42.99x = 1,859.76
5. Step 5: Solve for x
   x = 1,859.76/42.99
6. Step 6: Final answer
   x = 43.26