Home / 254.28-380.90-138.66

Finding the Fourth Proportional to 254.28, 380.90 and 138.66

Calculator

Solution

The fourth proportional to 254.28, 380.90 and 138.66 is: 207.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    254.28 : 380.90 = 138.66 : x
  2. Step 2: Convert to fraction form
    254.28/380.90 = 138.66/x
  3. Step 3: Cross multiply
    254.28x = 380.90 × 138.66
  4. Step 4: Simplify right side
    254.28x = 52,815.59
  5. Step 5: Solve for x
    x = 52,815.59/254.28
  6. Step 6: Final answer
    x = 207.71

Related Problems

Find fourth proportional to 127.14, 190.45 and 69.33
Half scale
Find fourth proportional to 508.56, 761.80 and 277.32
Double scale
Find fourth proportional to 255.28, 382.40 and 139.66
Similar ratio
Find fourth proportional to 381.42, 571.35 and 207.99
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.