Finding the Fourth Proportional to 78.45, 117.76 and 45.99

Step by Step Solution

1. Step 1: Write the proportion equation
   78.45 : 117.76 = 45.99 : x
2. Step 2: Convert to fraction form
   78.45/117.76 = 45.99/x
3. Step 3: Cross multiply
   78.45x = 117.76 × 45.99
4. Step 4: Simplify right side
   78.45x = 5,414.96
5. Step 5: Solve for x
   x = 5,414.96/78.45
6. Step 6: Final answer
   x = 69.03