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Finding the Fourth Proportional to 515.65, 711.59 and 279.60

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Solution

The fourth proportional to 515.65, 711.59 and 279.60 is: 385.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.65 : 711.59 = 279.60 : x
  2. Step 2: Convert to fraction form
    515.65/711.59 = 279.60/x
  3. Step 3: Cross multiply
    515.65x = 711.59 × 279.60
  4. Step 4: Simplify right side
    515.65x = 198,962.86
  5. Step 5: Solve for x
    x = 198,962.86/515.65
  6. Step 6: Final answer
    x = 385.85

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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.