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Finding the Fourth Proportional to 430.81, 645.79 and 247.90

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Solution

The fourth proportional to 430.81, 645.79 and 247.90 is: 371.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.81 : 645.79 = 247.90 : x
  2. Step 2: Convert to fraction form
    430.81/645.79 = 247.90/x
  3. Step 3: Cross multiply
    430.81x = 645.79 × 247.90
  4. Step 4: Simplify right side
    430.81x = 160,091.34
  5. Step 5: Solve for x
    x = 160,091.34/430.81
  6. Step 6: Final answer
    x = 371.61

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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.