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Finding the Fourth Proportional to 645.45, 969.97 and 385.48

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Solution

The fourth proportional to 645.45, 969.97 and 385.48 is: 579.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.45 : 969.97 = 385.48 : x
  2. Step 2: Convert to fraction form
    645.45/969.97 = 385.48/x
  3. Step 3: Cross multiply
    645.45x = 969.97 × 385.48
  4. Step 4: Simplify right side
    645.45x = 373,904.04
  5. Step 5: Solve for x
    x = 373,904.04/645.45
  6. Step 6: Final answer
    x = 579.29

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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.