Home / 487.20-731.10-213.42

Finding the Fourth Proportional to 487.20, 731.10 and 213.42

Calculator

Solution

The fourth proportional to 487.20, 731.10 and 213.42 is: 320.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.20 : 731.10 = 213.42 : x
  2. Step 2: Convert to fraction form
    487.20/731.10 = 213.42/x
  3. Step 3: Cross multiply
    487.20x = 731.10 × 213.42
  4. Step 4: Simplify right side
    487.20x = 156,031.36
  5. Step 5: Solve for x
    x = 156,031.36/487.20
  6. Step 6: Final answer
    x = 320.26

Related Problems

Find fourth proportional to 243.60, 365.55 and 106.71
Half scale
Find fourth proportional to 974.40, 1,462.20 and 426.84
Double scale
Find fourth proportional to 488.20, 732.60 and 214.42
Similar ratio
Find fourth proportional to 730.80, 1,096.65 and 320.13
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.