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Finding the Fourth Proportional to 101.02, 138.74 and 90.08

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Solution

The fourth proportional to 101.02, 138.74 and 90.08 is: 123.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.02 : 138.74 = 90.08 : x
  2. Step 2: Convert to fraction form
    101.02/138.74 = 90.08/x
  3. Step 3: Cross multiply
    101.02x = 138.74 × 90.08
  4. Step 4: Simplify right side
    101.02x = 12,497.70
  5. Step 5: Solve for x
    x = 12,497.70/101.02
  6. Step 6: Final answer
    x = 123.72

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.