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Finding the Fourth Proportional to 421.47, 631.19 and 340.47

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Solution

The fourth proportional to 421.47, 631.19 and 340.47 is: 509.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.47 : 631.19 = 340.47 : x
  2. Step 2: Convert to fraction form
    421.47/631.19 = 340.47/x
  3. Step 3: Cross multiply
    421.47x = 631.19 × 340.47
  4. Step 4: Simplify right side
    421.47x = 214,899.56
  5. Step 5: Solve for x
    x = 214,899.56/421.47
  6. Step 6: Final answer
    x = 509.88

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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.