Home / 254.90-381.90-209.18

Finding the Fourth Proportional to 254.90, 381.90 and 209.18

Calculator

Solution

The fourth proportional to 254.90, 381.90 and 209.18 is: 313.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    254.90 : 381.90 = 209.18 : x
  2. Step 2: Convert to fraction form
    254.90/381.90 = 209.18/x
  3. Step 3: Cross multiply
    254.90x = 381.90 × 209.18
  4. Step 4: Simplify right side
    254.90x = 79,885.84
  5. Step 5: Solve for x
    x = 79,885.84/254.90
  6. Step 6: Final answer
    x = 313.40

Related Problems

Find fourth proportional to 127.45, 190.95 and 104.59
Half scale
Find fourth proportional to 509.80, 763.80 and 418.36
Double scale
Find fourth proportional to 255.90, 383.40 and 210.18
Similar ratio
Find fourth proportional to 382.35, 572.85 and 313.77
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.