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Finding the Fourth Proportional to 645.32, 890.79 and 436.09

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Solution

The fourth proportional to 645.32, 890.79 and 436.09 is: 601.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.32 : 890.79 = 436.09 : x
  2. Step 2: Convert to fraction form
    645.32/890.79 = 436.09/x
  3. Step 3: Cross multiply
    645.32x = 890.79 × 436.09
  4. Step 4: Simplify right side
    645.32x = 388,466.84
  5. Step 5: Solve for x
    x = 388,466.84/645.32
  6. Step 6: Final answer
    x = 601.98

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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.