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Finding the Fourth Proportional to 431.65, 647.62 and 171.56

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Solution

The fourth proportional to 431.65, 647.62 and 171.56 is: 257.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    431.65 : 647.62 = 171.56 : x
  2. Step 2: Convert to fraction form
    431.65/647.62 = 171.56/x
  3. Step 3: Cross multiply
    431.65x = 647.62 × 171.56
  4. Step 4: Simplify right side
    431.65x = 111,107.74
  5. Step 5: Solve for x
    x = 111,107.74/431.65
  6. Step 6: Final answer
    x = 257.40

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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.