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Finding the Fourth Proportional to 430.18, 645.28 and 105.55

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Solution

The fourth proportional to 430.18, 645.28 and 105.55 is: 158.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.18 : 645.28 = 105.55 : x
  2. Step 2: Convert to fraction form
    430.18/645.28 = 105.55/x
  3. Step 3: Cross multiply
    430.18x = 645.28 × 105.55
  4. Step 4: Simplify right side
    430.18x = 68,106.08
  5. Step 5: Solve for x
    x = 68,106.08/430.18
  6. Step 6: Final answer
    x = 158.32

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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.