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Finding the Fourth Proportional to 870.06, 1,305.10 and 665

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Solution

The fourth proportional to 870.06, 1,305.10 and 665 is: 997.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.06 : 1,305.10 = 665 : x
  2. Step 2: Convert to fraction form
    870.06/1,305.10 = 665/x
  3. Step 3: Cross multiply
    870.06x = 1,305.10 × 665
  4. Step 4: Simplify right side
    870.06x = 867,891.50
  5. Step 5: Solve for x
    x = 867,891.50/870.06
  6. Step 6: Final answer
    x = 997.51

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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.