Home / 48.20-72.28-19.72

Finding the Fourth Proportional to 48.20, 72.28 and 19.72

Calculator

Solution

The fourth proportional to 48.20, 72.28 and 19.72 is: 29.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    48.20 : 72.28 = 19.72 : x
  2. Step 2: Convert to fraction form
    48.20/72.28 = 19.72/x
  3. Step 3: Cross multiply
    48.20x = 72.28 × 19.72
  4. Step 4: Simplify right side
    48.20x = 1,425.36
  5. Step 5: Solve for x
    x = 1,425.36/48.20
  6. Step 6: Final answer
    x = 29.57

Related Problems

Find fourth proportional to 24.10, 36.14 and 9.86
Half scale
Find fourth proportional to 96.40, 144.56 and 39.44
Double scale
Find fourth proportional to 49.20, 73.78 and 20.72
Similar ratio
Find fourth proportional to 72.30, 108.42 and 29.58
1.5x scale

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.