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Finding the Fourth Proportional to 645.16, 890.03 and 396.39

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Solution

The fourth proportional to 645.16, 890.03 and 396.39 is: 546.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.16 : 890.03 = 396.39 : x
  2. Step 2: Convert to fraction form
    645.16/890.03 = 396.39/x
  3. Step 3: Cross multiply
    645.16x = 890.03 × 396.39
  4. Step 4: Simplify right side
    645.16x = 352,798.99
  5. Step 5: Solve for x
    x = 352,798.99/645.16
  6. Step 6: Final answer
    x = 546.84

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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.