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Finding the Fourth Proportional to 421.80, 630.25 and 322.42

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Solution

The fourth proportional to 421.80, 630.25 and 322.42 is: 481.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.80 : 630.25 = 322.42 : x
  2. Step 2: Convert to fraction form
    421.80/630.25 = 322.42/x
  3. Step 3: Cross multiply
    421.80x = 630.25 × 322.42
  4. Step 4: Simplify right side
    421.80x = 203,206.40
  5. Step 5: Solve for x
    x = 203,206.40/421.80
  6. Step 6: Final answer
    x = 481.76

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.