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Finding the Fourth Proportional to 421.20, 630.68 and 334.80

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Solution

The fourth proportional to 421.20, 630.68 and 334.80 is: 501.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.20 : 630.68 = 334.80 : x
  2. Step 2: Convert to fraction form
    421.20/630.68 = 334.80/x
  3. Step 3: Cross multiply
    421.20x = 630.68 × 334.80
  4. Step 4: Simplify right side
    421.20x = 211,151.66
  5. Step 5: Solve for x
    x = 211,151.66/421.20
  6. Step 6: Final answer
    x = 501.31

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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.