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Finding the Fourth Proportional to 429.03, 643.16 and 209.53

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Solution

The fourth proportional to 429.03, 643.16 and 209.53 is: 314.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.03 : 643.16 = 209.53 : x
  2. Step 2: Convert to fraction form
    429.03/643.16 = 209.53/x
  3. Step 3: Cross multiply
    429.03x = 643.16 × 209.53
  4. Step 4: Simplify right side
    429.03x = 134,761.86
  5. Step 5: Solve for x
    x = 134,761.86/429.03
  6. Step 6: Final answer
    x = 314.11

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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.