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Finding the Fourth Proportional to 8.90, 13.28 and 7.49

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Solution

The fourth proportional to 8.90, 13.28 and 7.49 is: 11.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.90 : 13.28 = 7.49 : x
  2. Step 2: Convert to fraction form
    8.90/13.28 = 7.49/x
  3. Step 3: Cross multiply
    8.90x = 13.28 × 7.49
  4. Step 4: Simplify right side
    8.90x = 99.40
  5. Step 5: Solve for x
    x = 99.40/8.90
  6. Step 6: Final answer
    x = 11.17

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.