Finding the Fourth Proportional to 101.32, 139.59 and 77.98

Step by Step Solution

1. Step 1: Write the proportion equation
   101.32 : 139.59 = 77.98 : x
2. Step 2: Convert to fraction form
   101.32/139.59 = 77.98/x
3. Step 3: Cross multiply
   101.32x = 139.59 × 77.98
4. Step 4: Simplify right side
   101.32x = 10,885.23
5. Step 5: Solve for x
   x = 10,885.23/101.32
6. Step 6: Final answer
   x = 107.43