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Finding the Fourth Proportional to 645.12, 890.28 and 365.36

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Solution

The fourth proportional to 645.12, 890.28 and 365.36 is: 504.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.12 : 890.28 = 365.36 : x
  2. Step 2: Convert to fraction form
    645.12/890.28 = 365.36/x
  3. Step 3: Cross multiply
    645.12x = 890.28 × 365.36
  4. Step 4: Simplify right side
    645.12x = 325,268.25
  5. Step 5: Solve for x
    x = 325,268.25/645.12
  6. Step 6: Final answer
    x = 504.20

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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.