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Finding the Third Proportional to 642.07 and 870.08

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Solution

The third proportional to 642.07 and 870.08 is: 1,179.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.07 : 870.08 = 870.08 : x
  2. Step 2: Convert to fraction form
    642.07/870.08 = 870.08/x
  3. Step 3: Cross multiply
    642.07x = 870.08 × 870.08
  4. Step 4: Simplify right side
    642.07x = 757,035.09
  5. Step 5: Solve for x
    x = 757,035.09/642.07
  6. Step 6: Final answer
    x = 1,179.06

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.