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Finding the Fourth Proportional to 654.20, 981.42 and 345.80

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Solution

The fourth proportional to 654.20, 981.42 and 345.80 is: 518.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.20 : 981.42 = 345.80 : x
  2. Step 2: Convert to fraction form
    654.20/981.42 = 345.80/x
  3. Step 3: Cross multiply
    654.20x = 981.42 × 345.80
  4. Step 4: Simplify right side
    654.20x = 339,375.04
  5. Step 5: Solve for x
    x = 339,375.04/654.20
  6. Step 6: Final answer
    x = 518.76

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1.5x scale

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.