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Finding the Fourth Proportional to 430.26, 645.39 and 105.63

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Solution

The fourth proportional to 430.26, 645.39 and 105.63 is: 158.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.26 : 645.39 = 105.63 : x
  2. Step 2: Convert to fraction form
    430.26/645.39 = 105.63/x
  3. Step 3: Cross multiply
    430.26x = 645.39 × 105.63
  4. Step 4: Simplify right side
    430.26x = 68,172.55
  5. Step 5: Solve for x
    x = 68,172.55/430.26
  6. Step 6: Final answer
    x = 158.45

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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.