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Finding the Fourth Proportional to 645.38, 890.53 and 361.79

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Solution

The fourth proportional to 645.38, 890.53 and 361.79 is: 499.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.38 : 890.53 = 361.79 : x
  2. Step 2: Convert to fraction form
    645.38/890.53 = 361.79/x
  3. Step 3: Cross multiply
    645.38x = 890.53 × 361.79
  4. Step 4: Simplify right side
    645.38x = 322,184.85
  5. Step 5: Solve for x
    x = 322,184.85/645.38
  6. Step 6: Final answer
    x = 499.22

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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.