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Finding the Fourth Proportional to 306.80, 423.24 and 256.40

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Solution

The fourth proportional to 306.80, 423.24 and 256.40 is: 353.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.80 : 423.24 = 256.40 : x
  2. Step 2: Convert to fraction form
    306.80/423.24 = 256.40/x
  3. Step 3: Cross multiply
    306.80x = 423.24 × 256.40
  4. Step 4: Simplify right side
    306.80x = 108,518.74
  5. Step 5: Solve for x
    x = 108,518.74/306.80
  6. Step 6: Final answer
    x = 353.71

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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.