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Finding the Fourth Proportional to 389.04, 583.45 and 320.40

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Solution

The fourth proportional to 389.04, 583.45 and 320.40 is: 480.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.04 : 583.45 = 320.40 : x
  2. Step 2: Convert to fraction form
    389.04/583.45 = 320.40/x
  3. Step 3: Cross multiply
    389.04x = 583.45 × 320.40
  4. Step 4: Simplify right side
    389.04x = 186,933.66
  5. Step 5: Solve for x
    x = 186,933.66/389.04
  6. Step 6: Final answer
    x = 480.50

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.