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Finding the Fourth Proportional to 641.81, 885.71 and 379.89

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Solution

The fourth proportional to 641.81, 885.71 and 379.89 is: 524.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.81 : 885.71 = 379.89 : x
  2. Step 2: Convert to fraction form
    641.81/885.71 = 379.89/x
  3. Step 3: Cross multiply
    641.81x = 885.71 × 379.89
  4. Step 4: Simplify right side
    641.81x = 336,473.32
  5. Step 5: Solve for x
    x = 336,473.32/641.81
  6. Step 6: Final answer
    x = 524.25

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.