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Finding the Fourth Proportional to 80.49, 111.08 and 49.40

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Solution

The fourth proportional to 80.49, 111.08 and 49.40 is: 68.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.49 : 111.08 = 49.40 : x
  2. Step 2: Convert to fraction form
    80.49/111.08 = 49.40/x
  3. Step 3: Cross multiply
    80.49x = 111.08 × 49.40
  4. Step 4: Simplify right side
    80.49x = 5,487.51
  5. Step 5: Solve for x
    x = 5,487.51/80.49
  6. Step 6: Final answer
    x = 68.18

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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.