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Finding the Fourth Proportional to 429.30, 641.12 and 340.91

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Solution

The fourth proportional to 429.30, 641.12 and 340.91 is: 509.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.30 : 641.12 = 340.91 : x
  2. Step 2: Convert to fraction form
    429.30/641.12 = 340.91/x
  3. Step 3: Cross multiply
    429.30x = 641.12 × 340.91
  4. Step 4: Simplify right side
    429.30x = 218,561.71
  5. Step 5: Solve for x
    x = 218,561.71/429.30
  6. Step 6: Final answer
    x = 509.11

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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.