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Finding the Fourth Proportional to 210.71, 290.67 and 127.80

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Solution

The fourth proportional to 210.71, 290.67 and 127.80 is: 176.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.71 : 290.67 = 127.80 : x
  2. Step 2: Convert to fraction form
    210.71/290.67 = 127.80/x
  3. Step 3: Cross multiply
    210.71x = 290.67 × 127.80
  4. Step 4: Simplify right side
    210.71x = 37,147.63
  5. Step 5: Solve for x
    x = 37,147.63/210.71
  6. Step 6: Final answer
    x = 176.30

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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.