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Finding the Fourth Proportional to 427.30, 641.28 and 210.76

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Solution

The fourth proportional to 427.30, 641.28 and 210.76 is: 316.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.30 : 641.28 = 210.76 : x
  2. Step 2: Convert to fraction form
    427.30/641.28 = 210.76/x
  3. Step 3: Cross multiply
    427.30x = 641.28 × 210.76
  4. Step 4: Simplify right side
    427.30x = 135,156.17
  5. Step 5: Solve for x
    x = 135,156.17/427.30
  6. Step 6: Final answer
    x = 316.30

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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.