Finding the Fourth Proportional to 72.91, 100.65 and 53.50

Step by Step Solution

1. Step 1: Write the proportion equation
   72.91 : 100.65 = 53.50 : x
2. Step 2: Convert to fraction form
   72.91/100.65 = 53.50/x
3. Step 3: Cross multiply
   72.91x = 100.65 × 53.50
4. Step 4: Simplify right side
   72.91x = 5,384.78
5. Step 5: Solve for x
   x = 5,384.78/72.91
6. Step 6: Final answer
   x = 73.86