Home / 266.90-399.82-212.15

Finding the Fourth Proportional to 266.90, 399.82 and 212.15

Calculator

Solution

The fourth proportional to 266.90, 399.82 and 212.15 is: 317.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    266.90 : 399.82 = 212.15 : x
  2. Step 2: Convert to fraction form
    266.90/399.82 = 212.15/x
  3. Step 3: Cross multiply
    266.90x = 399.82 × 212.15
  4. Step 4: Simplify right side
    266.90x = 84,818.75
  5. Step 5: Solve for x
    x = 84,818.75/266.90
  6. Step 6: Final answer
    x = 317.79

Related Problems

Find fourth proportional to 133.45, 199.91 and 106.07
Half scale
Find fourth proportional to 533.80, 799.63 and 424.29
Double scale
Find fourth proportional to 267.90, 401.31 and 213.15
Similar ratio
Find fourth proportional to 400.35, 599.72 and 318.22
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.