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Finding the Fourth Proportional to 210.47, 315.77 and 82.31

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Solution

The fourth proportional to 210.47, 315.77 and 82.31 is: 123.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.47 : 315.77 = 82.31 : x
  2. Step 2: Convert to fraction form
    210.47/315.77 = 82.31/x
  3. Step 3: Cross multiply
    210.47x = 315.77 × 82.31
  4. Step 4: Simplify right side
    210.47x = 25,990.62
  5. Step 5: Solve for x
    x = 25,990.62/210.47
  6. Step 6: Final answer
    x = 123.49

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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.