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Finding the Fourth Proportional to 101.70, 151.71 and 87.90

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Solution

The fourth proportional to 101.70, 151.71 and 87.90 is: 131.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.70 : 151.71 = 87.90 : x
  2. Step 2: Convert to fraction form
    101.70/151.71 = 87.90/x
  3. Step 3: Cross multiply
    101.70x = 151.71 × 87.90
  4. Step 4: Simplify right side
    101.70x = 13,335.31
  5. Step 5: Solve for x
    x = 13,335.31/101.70
  6. Step 6: Final answer
    x = 131.12

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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.