Finding the Fourth Proportional to 77.31, 106.69 and 42.81

Step by Step Solution

1. Step 1: Write the proportion equation
   77.31 : 106.69 = 42.81 : x
2. Step 2: Convert to fraction form
   77.31/106.69 = 42.81/x
3. Step 3: Cross multiply
   77.31x = 106.69 × 42.81
4. Step 4: Simplify right side
   77.31x = 4,567.40
5. Step 5: Solve for x
   x = 4,567.40/77.31
6. Step 6: Final answer
   x = 59.08