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Finding the Fourth Proportional to 430.40, 645.62 and 170.35

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Solution

The fourth proportional to 430.40, 645.62 and 170.35 is: 255.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.40 : 645.62 = 170.35 : x
  2. Step 2: Convert to fraction form
    430.40/645.62 = 170.35/x
  3. Step 3: Cross multiply
    430.40x = 645.62 × 170.35
  4. Step 4: Simplify right side
    430.40x = 109,978.90
  5. Step 5: Solve for x
    x = 109,978.90/430.40
  6. Step 6: Final answer
    x = 255.53

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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.