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Finding the Fourth Proportional to 636.21, 877.70 and 387.47

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Solution

The fourth proportional to 636.21, 877.70 and 387.47 is: 534.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.21 : 877.70 = 387.47 : x
  2. Step 2: Convert to fraction form
    636.21/877.70 = 387.47/x
  3. Step 3: Cross multiply
    636.21x = 877.70 × 387.47
  4. Step 4: Simplify right side
    636.21x = 340,085.58
  5. Step 5: Solve for x
    x = 340,085.58/636.21
  6. Step 6: Final answer
    x = 534.55

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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.