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Finding the Fourth Proportional to 515.64, 711.57 and 279.57

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Solution

The fourth proportional to 515.64, 711.57 and 279.57 is: 385.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.64 : 711.57 = 279.57 : x
  2. Step 2: Convert to fraction form
    515.64/711.57 = 279.57/x
  3. Step 3: Cross multiply
    515.64x = 711.57 × 279.57
  4. Step 4: Simplify right side
    515.64x = 198,935.91
  5. Step 5: Solve for x
    x = 198,935.91/515.64
  6. Step 6: Final answer
    x = 385.81

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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.