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Finding the Fourth Proportional to 320.64, 480.24 and 258.96

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Solution

The fourth proportional to 320.64, 480.24 and 258.96 is: 387.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.64 : 480.24 = 258.96 : x
  2. Step 2: Convert to fraction form
    320.64/480.24 = 258.96/x
  3. Step 3: Cross multiply
    320.64x = 480.24 × 258.96
  4. Step 4: Simplify right side
    320.64x = 124,362.95
  5. Step 5: Solve for x
    x = 124,362.95/320.64
  6. Step 6: Final answer
    x = 387.86

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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.