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Finding the Fourth Proportional to 210.61, 290.70 and 123.31

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Solution

The fourth proportional to 210.61, 290.70 and 123.31 is: 170.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.61 : 290.70 = 123.31 : x
  2. Step 2: Convert to fraction form
    210.61/290.70 = 123.31/x
  3. Step 3: Cross multiply
    210.61x = 290.70 × 123.31
  4. Step 4: Simplify right side
    210.61x = 35,844.76
  5. Step 5: Solve for x
    x = 35,844.76/210.61
  6. Step 6: Final answer
    x = 170.20

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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.