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Finding the Fourth Proportional to 421.04, 630.84 and 339.92

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Solution

The fourth proportional to 421.04, 630.84 and 339.92 is: 509.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.04 : 630.84 = 339.92 : x
  2. Step 2: Convert to fraction form
    421.04/630.84 = 339.92/x
  3. Step 3: Cross multiply
    421.04x = 630.84 × 339.92
  4. Step 4: Simplify right side
    421.04x = 214,435.13
  5. Step 5: Solve for x
    x = 214,435.13/421.04
  6. Step 6: Final answer
    x = 509.30

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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.