Finding the Fourth Proportional to 71.25, 106.90 and 53.00

Step by Step Solution

1. Step 1: Write the proportion equation
   71.25 : 106.90 = 53.00 : x
2. Step 2: Convert to fraction form
   71.25/106.90 = 53.00/x
3. Step 3: Cross multiply
   71.25x = 106.90 × 53.00
4. Step 4: Simplify right side
   71.25x = 5,665.83
5. Step 5: Solve for x
   x = 5,665.83/71.25
6. Step 6: Final answer
   x = 79.52