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Finding the Fourth Proportional to 91.39, 126.12 and 71.75

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Solution

The fourth proportional to 91.39, 126.12 and 71.75 is: 99.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    91.39 : 126.12 = 71.75 : x
  2. Step 2: Convert to fraction form
    91.39/126.12 = 71.75/x
  3. Step 3: Cross multiply
    91.39x = 126.12 × 71.75
  4. Step 4: Simplify right side
    91.39x = 9,048.48
  5. Step 5: Solve for x
    x = 9,048.48/91.39
  6. Step 6: Final answer
    x = 99.01

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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.