Finding the Fourth Proportional to 100.54, 150.72 and 78.76

Step by Step Solution

1. Step 1: Write the proportion equation
   100.54 : 150.72 = 78.76 : x
2. Step 2: Convert to fraction form
   100.54/150.72 = 78.76/x
3. Step 3: Cross multiply
   100.54x = 150.72 × 78.76
4. Step 4: Simplify right side
   100.54x = 11,870.71
5. Step 5: Solve for x
   x = 11,870.71/100.54
6. Step 6: Final answer
   x = 118.07