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Finding the Fourth Proportional to 609.85, 841.35 and 389.08

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Solution

The fourth proportional to 609.85, 841.35 and 389.08 is: 536.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.85 : 841.35 = 389.08 : x
  2. Step 2: Convert to fraction form
    609.85/841.35 = 389.08/x
  3. Step 3: Cross multiply
    609.85x = 841.35 × 389.08
  4. Step 4: Simplify right side
    609.85x = 327,352.46
  5. Step 5: Solve for x
    x = 327,352.46/609.85
  6. Step 6: Final answer
    x = 536.78

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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.