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Finding the Fourth Proportional to 515.71, 771.88 and 378.72

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Solution

The fourth proportional to 515.71, 771.88 and 378.72 is: 566.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.71 : 771.88 = 378.72 : x
  2. Step 2: Convert to fraction form
    515.71/771.88 = 378.72/x
  3. Step 3: Cross multiply
    515.71x = 771.88 × 378.72
  4. Step 4: Simplify right side
    515.71x = 292,326.39
  5. Step 5: Solve for x
    x = 292,326.39/515.71
  6. Step 6: Final answer
    x = 566.84

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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.