Finding the Fourth Proportional to 76.50, 114.48 and 42.18

Step by Step Solution

1. Step 1: Write the proportion equation
   76.50 : 114.48 = 42.18 : x
2. Step 2: Convert to fraction form
   76.50/114.48 = 42.18/x
3. Step 3: Cross multiply
   76.50x = 114.48 × 42.18
4. Step 4: Simplify right side
   76.50x = 4,828.77
5. Step 5: Solve for x
   x = 4,828.77/76.50
6. Step 6: Final answer
   x = 63.12