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Finding the Fourth Proportional to 485.45, 669.97 and 288.96

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Solution

The fourth proportional to 485.45, 669.97 and 288.96 is: 398.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.45 : 669.97 = 288.96 : x
  2. Step 2: Convert to fraction form
    485.45/669.97 = 288.96/x
  3. Step 3: Cross multiply
    485.45x = 669.97 × 288.96
  4. Step 4: Simplify right side
    485.45x = 193,594.53
  5. Step 5: Solve for x
    x = 193,594.53/485.45
  6. Step 6: Final answer
    x = 398.80

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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.