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Finding the Fourth Proportional to 210.78, 290.87 and 127.87

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Solution

The fourth proportional to 210.78, 290.87 and 127.87 is: 176.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.78 : 290.87 = 127.87 : x
  2. Step 2: Convert to fraction form
    210.78/290.87 = 127.87/x
  3. Step 3: Cross multiply
    210.78x = 290.87 × 127.87
  4. Step 4: Simplify right side
    210.78x = 37,193.55
  5. Step 5: Solve for x
    x = 37,193.55/210.78
  6. Step 6: Final answer
    x = 176.46

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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.