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Finding the Fourth Proportional to 456.34, 684.51 and 212.80

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Solution

The fourth proportional to 456.34, 684.51 and 212.80 is: 319.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    456.34 : 684.51 = 212.80 : x
  2. Step 2: Convert to fraction form
    456.34/684.51 = 212.80/x
  3. Step 3: Cross multiply
    456.34x = 684.51 × 212.80
  4. Step 4: Simplify right side
    456.34x = 145,663.73
  5. Step 5: Solve for x
    x = 145,663.73/456.34
  6. Step 6: Final answer
    x = 319.20

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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.