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Finding the Fourth Proportional to 645.30, 884.12 and 636.19

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Solution

The fourth proportional to 645.30, 884.12 and 636.19 is: 871.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 884.12 = 636.19 : x
  2. Step 2: Convert to fraction form
    645.30/884.12 = 636.19/x
  3. Step 3: Cross multiply
    645.30x = 884.12 × 636.19
  4. Step 4: Simplify right side
    645.30x = 562,462.91
  5. Step 5: Solve for x
    x = 562,462.91/645.30
  6. Step 6: Final answer
    x = 871.63

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.