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Finding the Fourth Proportional to 645.09, 890.21 and 350.35

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Solution

The fourth proportional to 645.09, 890.21 and 350.35 is: 483.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.09 : 890.21 = 350.35 : x
  2. Step 2: Convert to fraction form
    645.09/890.21 = 350.35/x
  3. Step 3: Cross multiply
    645.09x = 890.21 × 350.35
  4. Step 4: Simplify right side
    645.09x = 311,885.07
  5. Step 5: Solve for x
    x = 311,885.07/645.09
  6. Step 6: Final answer
    x = 483.48

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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.