Home / 41.09-61.58-20.78

Finding the Fourth Proportional to 41.09, 61.58 and 20.78

Calculator

Solution

The fourth proportional to 41.09, 61.58 and 20.78 is: 31.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    41.09 : 61.58 = 20.78 : x
  2. Step 2: Convert to fraction form
    41.09/61.58 = 20.78/x
  3. Step 3: Cross multiply
    41.09x = 61.58 × 20.78
  4. Step 4: Simplify right side
    41.09x = 1,279.22
  5. Step 5: Solve for x
    x = 1,279.22/41.09
  6. Step 6: Final answer
    x = 31.14

Related Problems

Find fourth proportional to 20.54, 30.79 and 10.39
Half scale
Find fourth proportional to 82.17, 123.15 and 41.55
Double scale
Find fourth proportional to 42.09, 63.07 and 21.78
Similar ratio
Find fourth proportional to 61.63, 92.36 and 31.16
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.