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Finding the Fourth Proportional to 609.78, 841.25 and 388.86

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Solution

The fourth proportional to 609.78, 841.25 and 388.86 is: 536.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.78 : 841.25 = 388.86 : x
  2. Step 2: Convert to fraction form
    609.78/841.25 = 388.86/x
  3. Step 3: Cross multiply
    609.78x = 841.25 × 388.86
  4. Step 4: Simplify right side
    609.78x = 327,128.48
  5. Step 5: Solve for x
    x = 327,128.48/609.78
  6. Step 6: Final answer
    x = 536.47

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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.