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Finding the Fourth Proportional to 655.89, 979.73 and 643.74

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Solution

The fourth proportional to 655.89, 979.73 and 643.74 is: 961.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.89 : 979.73 = 643.74 : x
  2. Step 2: Convert to fraction form
    655.89/979.73 = 643.74/x
  3. Step 3: Cross multiply
    655.89x = 979.73 × 643.74
  4. Step 4: Simplify right side
    655.89x = 630,688.17
  5. Step 5: Solve for x
    x = 630,688.17/655.89
  6. Step 6: Final answer
    x = 961.58

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.