Finding the Fourth Proportional to 42.96, 64.71 and 42.60

Step by Step Solution

1. Step 1: Write the proportion equation
   42.96 : 64.71 = 42.60 : x
2. Step 2: Convert to fraction form
   42.96/64.71 = 42.60/x
3. Step 3: Cross multiply
   42.96x = 64.71 × 42.60
4. Step 4: Simplify right side
   42.96x = 2,756.65
5. Step 5: Solve for x
   x = 2,756.65/42.96
6. Step 6: Final answer
   x = 64.17