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Finding the Fourth Proportional to 1, 1.38 and 0.80

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Solution

The fourth proportional to 1, 1.38 and 0.80 is: 1.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    1 : 1.38 = 0.80 : x
  2. Step 2: Convert to fraction form
    1/1.38 = 0.80/x
  3. Step 3: Cross multiply
    1x = 1.38 × 0.80
  4. Step 4: Simplify right side
    1x = 1.10
  5. Step 5: Solve for x
    x = 1.10/1
  6. Step 6: Final answer
    x = 1.10

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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.