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Finding the Fourth Proportional to 321.60, 479.82 and 286.95

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Solution

The fourth proportional to 321.60, 479.82 and 286.95 is: 428.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.60 : 479.82 = 286.95 : x
  2. Step 2: Convert to fraction form
    321.60/479.82 = 286.95/x
  3. Step 3: Cross multiply
    321.60x = 479.82 × 286.95
  4. Step 4: Simplify right side
    321.60x = 137,684.35
  5. Step 5: Solve for x
    x = 137,684.35/321.60
  6. Step 6: Final answer
    x = 428.12

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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.