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Finding the Fourth Proportional to 389.40, 536.52 and 343.20

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Solution

The fourth proportional to 389.40, 536.52 and 343.20 is: 472.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.40 : 536.52 = 343.20 : x
  2. Step 2: Convert to fraction form
    389.40/536.52 = 343.20/x
  3. Step 3: Cross multiply
    389.40x = 536.52 × 343.20
  4. Step 4: Simplify right side
    389.40x = 184,133.66
  5. Step 5: Solve for x
    x = 184,133.66/389.40
  6. Step 6: Final answer
    x = 472.87

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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.