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Finding the Third Proportional to 5.31 and 8.40

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Solution

The third proportional to 5.31 and 8.40 is: 13.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.31 : 8.40 = 8.40 : x
  2. Step 2: Convert to fraction form
    5.31/8.40 = 8.40/x
  3. Step 3: Cross multiply
    5.31x = 8.40 × 8.40
  4. Step 4: Simplify right side
    5.31x = 70.60
  5. Step 5: Solve for x
    x = 70.60/5.31
  6. Step 6: Final answer
    x = 13.30

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Why These Related Problems?

These problems maintain the same ratio (1.58) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.