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Finding the Fourth Proportional to 643.05, 886.95 and 493.65

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Solution

The fourth proportional to 643.05, 886.95 and 493.65 is: 680.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.05 : 886.95 = 493.65 : x
  2. Step 2: Convert to fraction form
    643.05/886.95 = 493.65/x
  3. Step 3: Cross multiply
    643.05x = 886.95 × 493.65
  4. Step 4: Simplify right side
    643.05x = 437,842.87
  5. Step 5: Solve for x
    x = 437,842.87/643.05
  6. Step 6: Final answer
    x = 680.88

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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.