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Finding the Fourth Proportional to 512.66, 707.47 and 279.78

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Solution

The fourth proportional to 512.66, 707.47 and 279.78 is: 386.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.66 : 707.47 = 279.78 : x
  2. Step 2: Convert to fraction form
    512.66/707.47 = 279.78/x
  3. Step 3: Cross multiply
    512.66x = 707.47 × 279.78
  4. Step 4: Simplify right side
    512.66x = 197,935.96
  5. Step 5: Solve for x
    x = 197,935.96/512.66
  6. Step 6: Final answer
    x = 386.10

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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.