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Finding the Fourth Proportional to 430.64, 645.72 and 170.39

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Solution

The fourth proportional to 430.64, 645.72 and 170.39 is: 255.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.64 : 645.72 = 170.39 : x
  2. Step 2: Convert to fraction form
    430.64/645.72 = 170.39/x
  3. Step 3: Cross multiply
    430.64x = 645.72 × 170.39
  4. Step 4: Simplify right side
    430.64x = 110,024.23
  5. Step 5: Solve for x
    x = 110,024.23/430.64
  6. Step 6: Final answer
    x = 255.49

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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.