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Finding the Fourth Proportional to 630.21, 869.49 and 455.25

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Solution

The fourth proportional to 630.21, 869.49 and 455.25 is: 628.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.21 : 869.49 = 455.25 : x
  2. Step 2: Convert to fraction form
    630.21/869.49 = 455.25/x
  3. Step 3: Cross multiply
    630.21x = 869.49 × 455.25
  4. Step 4: Simplify right side
    630.21x = 395,835.32
  5. Step 5: Solve for x
    x = 395,835.32/630.21
  6. Step 6: Final answer
    x = 628.10

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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.