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Finding the Fourth Proportional to 430.16, 645.44 and 257.18

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Solution

The fourth proportional to 430.16, 645.44 and 257.18 is: 385.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.16 : 645.44 = 257.18 : x
  2. Step 2: Convert to fraction form
    430.16/645.44 = 257.18/x
  3. Step 3: Cross multiply
    430.16x = 645.44 × 257.18
  4. Step 4: Simplify right side
    430.16x = 165,994.26
  5. Step 5: Solve for x
    x = 165,994.26/430.16
  6. Step 6: Final answer
    x = 385.89

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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.