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Finding the Fourth Proportional to 210.66, 290.70 and 123.30

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Solution

The fourth proportional to 210.66, 290.70 and 123.30 is: 170.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.66 : 290.70 = 123.30 : x
  2. Step 2: Convert to fraction form
    210.66/290.70 = 123.30/x
  3. Step 3: Cross multiply
    210.66x = 290.70 × 123.30
  4. Step 4: Simplify right side
    210.66x = 35,843.31
  5. Step 5: Solve for x
    x = 35,843.31/210.66
  6. Step 6: Final answer
    x = 170.15

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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.