Finding the Fourth Proportional to 71.39, 107.00 and 42.50

Step by Step Solution

1. Step 1: Write the proportion equation
   71.39 : 107.00 = 42.50 : x
2. Step 2: Convert to fraction form
   71.39/107.00 = 42.50/x
3. Step 3: Cross multiply
   71.39x = 107.00 × 42.50
4. Step 4: Simplify right side
   71.39x = 4,547.29
5. Step 5: Solve for x
   x = 4,547.29/71.39
6. Step 6: Final answer
   x = 63.70