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Finding the Fourth Proportional to 10.10, 15.05 and 9.90

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Solution

The fourth proportional to 10.10, 15.05 and 9.90 is: 14.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.10 : 15.05 = 9.90 : x
  2. Step 2: Convert to fraction form
    10.10/15.05 = 9.90/x
  3. Step 3: Cross multiply
    10.10x = 15.05 × 9.90
  4. Step 4: Simplify right side
    10.10x = 149.02
  5. Step 5: Solve for x
    x = 149.02/10.10
  6. Step 6: Final answer
    x = 14.75

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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.