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Finding the Fourth Proportional to 389.21, 580.96 and 343.08

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Solution

The fourth proportional to 389.21, 580.96 and 343.08 is: 512.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.21 : 580.96 = 343.08 : x
  2. Step 2: Convert to fraction form
    389.21/580.96 = 343.08/x
  3. Step 3: Cross multiply
    389.21x = 580.96 × 343.08
  4. Step 4: Simplify right side
    389.21x = 199,312.85
  5. Step 5: Solve for x
    x = 199,312.85/389.21
  6. Step 6: Final answer
    x = 512.10

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.