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Finding the Fourth Proportional to 435.19, 647.82 and 428.71

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Solution

The fourth proportional to 435.19, 647.82 and 428.71 is: 638.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    435.19 : 647.82 = 428.71 : x
  2. Step 2: Convert to fraction form
    435.19/647.82 = 428.71/x
  3. Step 3: Cross multiply
    435.19x = 647.82 × 428.71
  4. Step 4: Simplify right side
    435.19x = 277,726.91
  5. Step 5: Solve for x
    x = 277,726.91/435.19
  6. Step 6: Final answer
    x = 638.17

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.