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Finding the Fourth Proportional to 5.15, 7.71 and 3.00

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Solution

The fourth proportional to 5.15, 7.71 and 3.00 is: 4.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.15 : 7.71 = 3.00 : x
  2. Step 2: Convert to fraction form
    5.15/7.71 = 3.00/x
  3. Step 3: Cross multiply
    5.15x = 7.71 × 3.00
  4. Step 4: Simplify right side
    5.15x = 23.14
  5. Step 5: Solve for x
    x = 23.14/5.15
  6. Step 6: Final answer
    x = 4.49

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.