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Finding the Fourth Proportional to 478.45, 660.27 and 289.45

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Solution

The fourth proportional to 478.45, 660.27 and 289.45 is: 399.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.45 : 660.27 = 289.45 : x
  2. Step 2: Convert to fraction form
    478.45/660.27 = 289.45/x
  3. Step 3: Cross multiply
    478.45x = 660.27 × 289.45
  4. Step 4: Simplify right side
    478.45x = 191,117.06
  5. Step 5: Solve for x
    x = 191,117.06/478.45
  6. Step 6: Final answer
    x = 399.45

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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.