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Finding the Fourth Proportional to 99.30, 138.75 and 99.30

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Solution

The fourth proportional to 99.30, 138.75 and 99.30 is: 138.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    99.30 : 138.75 = 99.30 : x
  2. Step 2: Convert to fraction form
    99.30/138.75 = 99.30/x
  3. Step 3: Cross multiply
    99.30x = 138.75 × 99.30
  4. Step 4: Simplify right side
    99.30x = 13,777.88
  5. Step 5: Solve for x
    x = 13,777.88/99.30
  6. Step 6: Final answer
    x = 138.75

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.