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Finding the Fourth Proportional to 426.39, 639.62 and 148.79

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Solution

The fourth proportional to 426.39, 639.62 and 148.79 is: 223.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.39 : 639.62 = 148.79 : x
  2. Step 2: Convert to fraction form
    426.39/639.62 = 148.79/x
  3. Step 3: Cross multiply
    426.39x = 639.62 × 148.79
  4. Step 4: Simplify right side
    426.39x = 95,169.06
  5. Step 5: Solve for x
    x = 95,169.06/426.39
  6. Step 6: Final answer
    x = 223.20

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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.