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Finding the Fourth Proportional to 430.08, 645.24 and 198.78

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Solution

The fourth proportional to 430.08, 645.24 and 198.78 is: 298.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.08 : 645.24 = 198.78 : x
  2. Step 2: Convert to fraction form
    430.08/645.24 = 198.78/x
  3. Step 3: Cross multiply
    430.08x = 645.24 × 198.78
  4. Step 4: Simplify right side
    430.08x = 128,260.81
  5. Step 5: Solve for x
    x = 128,260.81/430.08
  6. Step 6: Final answer
    x = 298.23

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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.