Home / 406.81-561.15-308.39

Finding the Fourth Proportional to 406.81, 561.15 and 308.39

Calculator

Solution

The fourth proportional to 406.81, 561.15 and 308.39 is: 425.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.81 : 561.15 = 308.39 : x
  2. Step 2: Convert to fraction form
    406.81/561.15 = 308.39/x
  3. Step 3: Cross multiply
    406.81x = 561.15 × 308.39
  4. Step 4: Simplify right side
    406.81x = 173,054.45
  5. Step 5: Solve for x
    x = 173,054.45/406.81
  6. Step 6: Final answer
    x = 425.40

Related Problems

Find fourth proportional to 203.40, 280.58 and 154.20
Half scale
Find fourth proportional to 813.62, 1,122.30 and 616.79
Double scale
Find fourth proportional to 407.81, 562.53 and 309.39
Similar ratio
Find fourth proportional to 610.21, 841.73 and 462.59
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.