Finding the Fourth Proportional to 70.31, 105.71 and 56.05

Step by Step Solution

1. Step 1: Write the proportion equation
   70.31 : 105.71 = 56.05 : x
2. Step 2: Convert to fraction form
   70.31/105.71 = 56.05/x
3. Step 3: Cross multiply
   70.31x = 105.71 × 56.05
4. Step 4: Simplify right side
   70.31x = 5,924.50
5. Step 5: Solve for x
   x = 5,924.50/70.31
6. Step 6: Final answer
   x = 84.26