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Finding the Fourth Proportional to 653.82, 979.90 and 345.21

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Solution

The fourth proportional to 653.82, 979.90 and 345.21 is: 517.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.82 : 979.90 = 345.21 : x
  2. Step 2: Convert to fraction form
    653.82/979.90 = 345.21/x
  3. Step 3: Cross multiply
    653.82x = 979.90 × 345.21
  4. Step 4: Simplify right side
    653.82x = 338,272.25
  5. Step 5: Solve for x
    x = 338,272.25/653.82
  6. Step 6: Final answer
    x = 517.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.