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Finding the Fourth Proportional to 487.78, 729.81 and 271.51

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Solution

The fourth proportional to 487.78, 729.81 and 271.51 is: 406.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.78 : 729.81 = 271.51 : x
  2. Step 2: Convert to fraction form
    487.78/729.81 = 271.51/x
  3. Step 3: Cross multiply
    487.78x = 729.81 × 271.51
  4. Step 4: Simplify right side
    487.78x = 198,150.71
  5. Step 5: Solve for x
    x = 198,150.71/487.78
  6. Step 6: Final answer
    x = 406.23

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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.