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Finding the Fourth Proportional to 645.53, 890.80 and 350.78

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Solution

The fourth proportional to 645.53, 890.80 and 350.78 is: 484.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.53 : 890.80 = 350.78 : x
  2. Step 2: Convert to fraction form
    645.53/890.80 = 350.78/x
  3. Step 3: Cross multiply
    645.53x = 890.80 × 350.78
  4. Step 4: Simplify right side
    645.53x = 312,469.49
  5. Step 5: Solve for x
    x = 312,469.49/645.53
  6. Step 6: Final answer
    x = 484.05

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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.