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Finding the Fourth Proportional to 643.60, 887.96 and 457.12

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Solution

The fourth proportional to 643.60, 887.96 and 457.12 is: 630.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.60 : 887.96 = 457.12 : x
  2. Step 2: Convert to fraction form
    643.60/887.96 = 457.12/x
  3. Step 3: Cross multiply
    643.60x = 887.96 × 457.12
  4. Step 4: Simplify right side
    643.60x = 405,904.28
  5. Step 5: Solve for x
    x = 405,904.28/643.60
  6. Step 6: Final answer
    x = 630.68

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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.