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Finding the Fourth Proportional to 306.40, 459.20 and 220.80

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Solution

The fourth proportional to 306.40, 459.20 and 220.80 is: 330.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.40 : 459.20 = 220.80 : x
  2. Step 2: Convert to fraction form
    306.40/459.20 = 220.80/x
  3. Step 3: Cross multiply
    306.40x = 459.20 × 220.80
  4. Step 4: Simplify right side
    306.40x = 101,391.36
  5. Step 5: Solve for x
    x = 101,391.36/306.40
  6. Step 6: Final answer
    x = 330.91

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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.