Finding the Fourth Proportional to 72.91, 100.37 and 56.53

Step by Step Solution

1. Step 1: Write the proportion equation
   72.91 : 100.37 = 56.53 : x
2. Step 2: Convert to fraction form
   72.91/100.37 = 56.53/x
3. Step 3: Cross multiply
   72.91x = 100.37 × 56.53
4. Step 4: Simplify right side
   72.91x = 5,673.13
5. Step 5: Solve for x
   x = 5,673.13/72.91
6. Step 6: Final answer
   x = 77.82