Home / 34.90-48.17-21.78

Finding the Fourth Proportional to 34.90, 48.17 and 21.78

Calculator

Solution

The fourth proportional to 34.90, 48.17 and 21.78 is: 30.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    34.90 : 48.17 = 21.78 : x
  2. Step 2: Convert to fraction form
    34.90/48.17 = 21.78/x
  3. Step 3: Cross multiply
    34.90x = 48.17 × 21.78
  4. Step 4: Simplify right side
    34.90x = 1,049.07
  5. Step 5: Solve for x
    x = 1,049.07/34.90
  6. Step 6: Final answer
    x = 30.06

Related Problems

Find fourth proportional to 17.45, 24.08 and 10.89
Half scale
Find fourth proportional to 69.81, 96.33 and 43.56
Double scale
Find fourth proportional to 35.90, 49.55 and 22.78
Similar ratio
Find fourth proportional to 52.35, 72.25 and 32.67
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.