Home / 455.20-631.40-439.66

Finding the Fourth Proportional to 455.20, 631.40 and 439.66

Calculator

Solution

The fourth proportional to 455.20, 631.40 and 439.66 is: 609.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    455.20 : 631.40 = 439.66 : x
  2. Step 2: Convert to fraction form
    455.20/631.40 = 439.66/x
  3. Step 3: Cross multiply
    455.20x = 631.40 × 439.66
  4. Step 4: Simplify right side
    455.20x = 277,601.32
  5. Step 5: Solve for x
    x = 277,601.32/455.20
  6. Step 6: Final answer
    x = 609.84

Related Problems

Find fourth proportional to 227.60, 315.70 and 219.83
Half scale
Find fourth proportional to 910.40, 1,262.80 and 879.32
Double scale
Find fourth proportional to 456.20, 632.79 and 440.66
Similar ratio
Find fourth proportional to 682.80, 947.10 and 659.49
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.