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Finding the Fourth Proportional to 609.21, 840.84 and 388.44

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Solution

The fourth proportional to 609.21, 840.84 and 388.44 is: 536.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.21 : 840.84 = 388.44 : x
  2. Step 2: Convert to fraction form
    609.21/840.84 = 388.44/x
  3. Step 3: Cross multiply
    609.21x = 840.84 × 388.44
  4. Step 4: Simplify right side
    609.21x = 326,615.89
  5. Step 5: Solve for x
    x = 326,615.89/609.21
  6. Step 6: Final answer
    x = 536.13

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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.