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Finding the Fourth Proportional to 641.79, 885.72 and 484.15

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Solution

The fourth proportional to 641.79, 885.72 and 484.15 is: 668.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.79 : 885.72 = 484.15 : x
  2. Step 2: Convert to fraction form
    641.79/885.72 = 484.15/x
  3. Step 3: Cross multiply
    641.79x = 885.72 × 484.15
  4. Step 4: Simplify right side
    641.79x = 428,814.49
  5. Step 5: Solve for x
    x = 428,814.49/641.79
  6. Step 6: Final answer
    x = 668.15

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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.