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Finding the Fourth Proportional to 71.98, 99.17 and 57.40

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Solution

The fourth proportional to 71.98, 99.17 and 57.40 is: 79.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.98 : 99.17 = 57.40 : x
  2. Step 2: Convert to fraction form
    71.98/99.17 = 57.40/x
  3. Step 3: Cross multiply
    71.98x = 99.17 × 57.40
  4. Step 4: Simplify right side
    71.98x = 5,692.07
  5. Step 5: Solve for x
    x = 5,692.07/71.98
  6. Step 6: Final answer
    x = 79.08

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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.