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Finding the Fourth Proportional to 641.70, 885.15 and 393.03

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Solution

The fourth proportional to 641.70, 885.15 and 393.03 is: 542.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.70 : 885.15 = 393.03 : x
  2. Step 2: Convert to fraction form
    641.70/885.15 = 393.03/x
  3. Step 3: Cross multiply
    641.70x = 885.15 × 393.03
  4. Step 4: Simplify right side
    641.70x = 347,890.50
  5. Step 5: Solve for x
    x = 347,890.50/641.70
  6. Step 6: Final answer
    x = 542.14

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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.