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Finding the Fourth Proportional to 12.70, 17.54 and 8.40

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Solution

The fourth proportional to 12.70, 17.54 and 8.40 is: 11.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.70 : 17.54 = 8.40 : x
  2. Step 2: Convert to fraction form
    12.70/17.54 = 8.40/x
  3. Step 3: Cross multiply
    12.70x = 17.54 × 8.40
  4. Step 4: Simplify right side
    12.70x = 147.34
  5. Step 5: Solve for x
    x = 147.34/12.70
  6. Step 6: Final answer
    x = 11.60

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.