Finding the Fourth Proportional to 42.99, 64.38 and 42.59

Step by Step Solution

1. Step 1: Write the proportion equation
   42.99 : 64.38 = 42.59 : x
2. Step 2: Convert to fraction form
   42.99/64.38 = 42.59/x
3. Step 3: Cross multiply
   42.99x = 64.38 × 42.59
4. Step 4: Simplify right side
   42.99x = 2,741.62
5. Step 5: Solve for x
   x = 2,741.62/42.99
6. Step 6: Final answer
   x = 63.77