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Finding the Fourth Proportional to 421.16, 630.28 and 290.56

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Solution

The fourth proportional to 421.16, 630.28 and 290.56 is: 434.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.16 : 630.28 = 290.56 : x
  2. Step 2: Convert to fraction form
    421.16/630.28 = 290.56/x
  3. Step 3: Cross multiply
    421.16x = 630.28 × 290.56
  4. Step 4: Simplify right side
    421.16x = 183,134.16
  5. Step 5: Solve for x
    x = 183,134.16/421.16
  6. Step 6: Final answer
    x = 434.83

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.