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Finding the Fourth Proportional to 641.71, 885.90 and 628.35

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Solution

The fourth proportional to 641.71, 885.90 and 628.35 is: 867.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.71 : 885.90 = 628.35 : x
  2. Step 2: Convert to fraction form
    641.71/885.90 = 628.35/x
  3. Step 3: Cross multiply
    641.71x = 885.90 × 628.35
  4. Step 4: Simplify right side
    641.71x = 556,655.27
  5. Step 5: Solve for x
    x = 556,655.27/641.71
  6. Step 6: Final answer
    x = 867.46

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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.