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Finding the Fourth Proportional to 210.70, 290.80 and 127.86

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Solution

The fourth proportional to 210.70, 290.80 and 127.86 is: 176.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.70 : 290.80 = 127.86 : x
  2. Step 2: Convert to fraction form
    210.70/290.80 = 127.86/x
  3. Step 3: Cross multiply
    210.70x = 290.80 × 127.86
  4. Step 4: Simplify right side
    210.70x = 37,181.69
  5. Step 5: Solve for x
    x = 37,181.69/210.70
  6. Step 6: Final answer
    x = 176.47

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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.