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Finding the Fourth Proportional to 99.70, 149.56 and 38.80

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Solution

The fourth proportional to 99.70, 149.56 and 38.80 is: 58.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    99.70 : 149.56 = 38.80 : x
  2. Step 2: Convert to fraction form
    99.70/149.56 = 38.80/x
  3. Step 3: Cross multiply
    99.70x = 149.56 × 38.80
  4. Step 4: Simplify right side
    99.70x = 5,802.39
  5. Step 5: Solve for x
    x = 5,802.39/99.70
  6. Step 6: Final answer
    x = 58.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.