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Finding the Fourth Proportional to 870, 1,305 and 292.88

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Solution

The fourth proportional to 870, 1,305 and 292.88 is: 439.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    870 : 1,305 = 292.88 : x
  2. Step 2: Convert to fraction form
    870/1,305 = 292.88/x
  3. Step 3: Cross multiply
    870x = 1,305 × 292.88
  4. Step 4: Simplify right side
    870x = 382,201.88
  5. Step 5: Solve for x
    x = 382,201.88/870
  6. Step 6: Final answer
    x = 439.31

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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.