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Finding the Fourth Proportional to 515.81, 711.82 and 279.76

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Solution

The fourth proportional to 515.81, 711.82 and 279.76 is: 386.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.81 : 711.82 = 279.76 : x
  2. Step 2: Convert to fraction form
    515.81/711.82 = 279.76/x
  3. Step 3: Cross multiply
    515.81x = 711.82 × 279.76
  4. Step 4: Simplify right side
    515.81x = 199,135.09
  5. Step 5: Solve for x
    x = 199,135.09/515.81
  6. Step 6: Final answer
    x = 386.07

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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.