Home / 34.39-51.52-20.86

Finding the Fourth Proportional to 34.39, 51.52 and 20.86

Calculator

Solution

The fourth proportional to 34.39, 51.52 and 20.86 is: 31.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    34.39 : 51.52 = 20.86 : x
  2. Step 2: Convert to fraction form
    34.39/51.52 = 20.86/x
  3. Step 3: Cross multiply
    34.39x = 51.52 × 20.86
  4. Step 4: Simplify right side
    34.39x = 1,074.71
  5. Step 5: Solve for x
    x = 1,074.71/34.39
  6. Step 6: Final answer
    x = 31.25

Related Problems

Find fourth proportional to 17.20, 25.76 and 10.43
Half scale
Find fourth proportional to 68.78, 103.04 and 41.72
Double scale
Find fourth proportional to 35.39, 53.02 and 21.86
Similar ratio
Find fourth proportional to 51.59, 77.28 and 31.29
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.