Finding the Fourth Proportional to 67.42, 100.88 and 53.80

Step by Step Solution

1. Step 1: Write the proportion equation
   67.42 : 100.88 = 53.80 : x
2. Step 2: Convert to fraction form
   67.42/100.88 = 53.80/x
3. Step 3: Cross multiply
   67.42x = 100.88 × 53.80
4. Step 4: Simplify right side
   67.42x = 5,427.34
5. Step 5: Solve for x
   x = 5,427.34/67.42
6. Step 6: Final answer
   x = 80.50