Finding the Fourth Proportional to 56.99, 78.60 and 42.01

Step by Step Solution

1. Step 1: Write the proportion equation
   56.99 : 78.60 = 42.01 : x
2. Step 2: Convert to fraction form
   56.99/78.60 = 42.01/x
3. Step 3: Cross multiply
   56.99x = 78.60 × 42.01
4. Step 4: Simplify right side
   56.99x = 3,301.95
5. Step 5: Solve for x
   x = 3,301.95/56.99
6. Step 6: Final answer
   x = 57.94