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Finding the Fourth Proportional to 478.89, 660.81 and 282.40

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Solution

The fourth proportional to 478.89, 660.81 and 282.40 is: 389.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.89 : 660.81 = 282.40 : x
  2. Step 2: Convert to fraction form
    478.89/660.81 = 282.40/x
  3. Step 3: Cross multiply
    478.89x = 660.81 × 282.40
  4. Step 4: Simplify right side
    478.89x = 186,612.74
  5. Step 5: Solve for x
    x = 186,612.74/478.89
  6. Step 6: Final answer
    x = 389.68

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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.