Home / 394.50-591.30-221.09

Finding the Fourth Proportional to 394.50, 591.30 and 221.09

Calculator

Solution

The fourth proportional to 394.50, 591.30 and 221.09 is: 331.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    394.50 : 591.30 = 221.09 : x
  2. Step 2: Convert to fraction form
    394.50/591.30 = 221.09/x
  3. Step 3: Cross multiply
    394.50x = 591.30 × 221.09
  4. Step 4: Simplify right side
    394.50x = 130,730.52
  5. Step 5: Solve for x
    x = 130,730.52/394.50
  6. Step 6: Final answer
    x = 331.38

Related Problems

Find fourth proportional to 197.25, 295.65 and 110.55
Half scale
Find fourth proportional to 789, 1,182.60 and 442.18
Double scale
Find fourth proportional to 395.50, 592.80 and 222.09
Similar ratio
Find fourth proportional to 591.75, 886.95 and 331.64
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.