Finding the Fourth Proportional to 90.63, 135.99 and 78.52

Step by Step Solution

1. Step 1: Write the proportion equation
   90.63 : 135.99 = 78.52 : x
2. Step 2: Convert to fraction form
   90.63/135.99 = 78.52/x
3. Step 3: Cross multiply
   90.63x = 135.99 × 78.52
4. Step 4: Simplify right side
   90.63x = 10,677.93
5. Step 5: Solve for x
   x = 10,677.93/90.63
6. Step 6: Final answer
   x = 117.82