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Finding the Fourth Proportional to 512.80, 707.66 and 279.92

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Solution

The fourth proportional to 512.80, 707.66 and 279.92 is: 386.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.80 : 707.66 = 279.92 : x
  2. Step 2: Convert to fraction form
    512.80/707.66 = 279.92/x
  3. Step 3: Cross multiply
    512.80x = 707.66 × 279.92
  4. Step 4: Simplify right side
    512.80x = 198,088.19
  5. Step 5: Solve for x
    x = 198,088.19/512.80
  6. Step 6: Final answer
    x = 386.29

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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.