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Finding the Fourth Proportional to 609.21, 840.78 and 347.36

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Solution

The fourth proportional to 609.21, 840.78 and 347.36 is: 479.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.21 : 840.78 = 347.36 : x
  2. Step 2: Convert to fraction form
    609.21/840.78 = 347.36/x
  3. Step 3: Cross multiply
    609.21x = 840.78 × 347.36
  4. Step 4: Simplify right side
    609.21x = 292,049.14
  5. Step 5: Solve for x
    x = 292,049.14/609.21
  6. Step 6: Final answer
    x = 479.39

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.