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Finding the Third Proportional to 287.81 and 407.91

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Solution

The third proportional to 287.81 and 407.91 is: 578.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.81 : 407.91 = 407.91 : x
  2. Step 2: Convert to fraction form
    287.81/407.91 = 407.91/x
  3. Step 3: Cross multiply
    287.81x = 407.91 × 407.91
  4. Step 4: Simplify right side
    287.81x = 166,387.51
  5. Step 5: Solve for x
    x = 166,387.51/287.81
  6. Step 6: Final answer
    x = 578.11

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Why These Related Problems?

These problems maintain the same ratio (1.42) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.