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Finding the Fourth Proportional to 430.14, 645.10 and 210.78

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Solution

The fourth proportional to 430.14, 645.10 and 210.78 is: 316.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.14 : 645.10 = 210.78 : x
  2. Step 2: Convert to fraction form
    430.14/645.10 = 210.78/x
  3. Step 3: Cross multiply
    430.14x = 645.10 × 210.78
  4. Step 4: Simplify right side
    430.14x = 135,974.18
  5. Step 5: Solve for x
    x = 135,974.18/430.14
  6. Step 6: Final answer
    x = 316.12

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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.