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Finding the Fourth Proportional to 90.05, 124.10 and 71.58

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Solution

The fourth proportional to 90.05, 124.10 and 71.58 is: 98.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.05 : 124.10 = 71.58 : x
  2. Step 2: Convert to fraction form
    90.05/124.10 = 71.58/x
  3. Step 3: Cross multiply
    90.05x = 124.10 × 71.58
  4. Step 4: Simplify right side
    90.05x = 8,883.45
  5. Step 5: Solve for x
    x = 8,883.45/90.05
  6. Step 6: Final answer
    x = 98.66

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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.