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Finding the Fourth Proportional to 429.17, 643.61 and 185.57

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Solution

The fourth proportional to 429.17, 643.61 and 185.57 is: 278.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.17 : 643.61 = 185.57 : x
  2. Step 2: Convert to fraction form
    429.17/643.61 = 185.57/x
  3. Step 3: Cross multiply
    429.17x = 643.61 × 185.57
  4. Step 4: Simplify right side
    429.17x = 119,430.56
  5. Step 5: Solve for x
    x = 119,430.56/429.17
  6. Step 6: Final answer
    x = 278.28

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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.