Home / 339.90-509.58-211.38

Finding the Fourth Proportional to 339.90, 509.58 and 211.38

Calculator

Solution

The fourth proportional to 339.90, 509.58 and 211.38 is: 316.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.90 : 509.58 = 211.38 : x
  2. Step 2: Convert to fraction form
    339.90/509.58 = 211.38/x
  3. Step 3: Cross multiply
    339.90x = 509.58 × 211.38
  4. Step 4: Simplify right side
    339.90x = 107,715.02
  5. Step 5: Solve for x
    x = 107,715.02/339.90
  6. Step 6: Final answer
    x = 316.90

Related Problems

Find fourth proportional to 169.95, 254.79 and 105.69
Half scale
Find fourth proportional to 679.80, 1,019.16 and 422.76
Double scale
Find fourth proportional to 340.90, 511.08 and 212.38
Similar ratio
Find fourth proportional to 509.85, 764.37 and 317.07
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.