Home / 81.09-121.57-42.53

Finding the Fourth Proportional to 81.09, 121.57 and 42.53

Calculator

Solution

The fourth proportional to 81.09, 121.57 and 42.53 is: 63.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.09 : 121.57 = 42.53 : x
  2. Step 2: Convert to fraction form
    81.09/121.57 = 42.53/x
  3. Step 3: Cross multiply
    81.09x = 121.57 × 42.53
  4. Step 4: Simplify right side
    81.09x = 5,169.66
  5. Step 5: Solve for x
    x = 5,169.66/81.09
  6. Step 6: Final answer
    x = 63.75

Related Problems

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.