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Finding the Fourth Proportional to 210.45, 290.47 and 123.15

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Solution

The fourth proportional to 210.45, 290.47 and 123.15 is: 169.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.45 : 290.47 = 123.15 : x
  2. Step 2: Convert to fraction form
    210.45/290.47 = 123.15/x
  3. Step 3: Cross multiply
    210.45x = 290.47 × 123.15
  4. Step 4: Simplify right side
    210.45x = 35,769.62
  5. Step 5: Solve for x
    x = 35,769.62/210.45
  6. Step 6: Final answer
    x = 169.97

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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.