Finding the Fourth Proportional to 143.50, 215.34 and 78.52

Step by Step Solution

1. Step 1: Write the proportion equation
   143.50 : 215.34 = 78.52 : x
2. Step 2: Convert to fraction form
   143.50/215.34 = 78.52/x
3. Step 3: Cross multiply
   143.50x = 215.34 × 78.52
4. Step 4: Simplify right side
   143.50x = 16,908.50
5. Step 5: Solve for x
   x = 16,908.50/143.50
6. Step 6: Final answer
   x = 117.83