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Finding the Fourth Proportional to 430.39, 645.57 and 211.18

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Solution

The fourth proportional to 430.39, 645.57 and 211.18 is: 316.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.39 : 645.57 = 211.18 : x
  2. Step 2: Convert to fraction form
    430.39/645.57 = 211.18/x
  3. Step 3: Cross multiply
    430.39x = 645.57 × 211.18
  4. Step 4: Simplify right side
    430.39x = 136,331.47
  5. Step 5: Solve for x
    x = 136,331.47/430.39
  6. Step 6: Final answer
    x = 316.76

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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.