Finding the Fourth Proportional to 123.96, 185.78 and 42.70

Step by Step Solution

1. Step 1: Write the proportion equation
   123.96 : 185.78 = 42.70 : x
2. Step 2: Convert to fraction form
   123.96/185.78 = 42.70/x
3. Step 3: Cross multiply
   123.96x = 185.78 × 42.70
4. Step 4: Simplify right side
   123.96x = 7,933.26
5. Step 5: Solve for x
   x = 7,933.26/123.96
6. Step 6: Final answer
   x = 64.00