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Finding the Fourth Proportional to 210.40, 290.31 and 123.10

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Solution

The fourth proportional to 210.40, 290.31 and 123.10 is: 169.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.40 : 290.31 = 123.10 : x
  2. Step 2: Convert to fraction form
    210.40/290.31 = 123.10/x
  3. Step 3: Cross multiply
    210.40x = 290.31 × 123.10
  4. Step 4: Simplify right side
    210.40x = 35,737.16
  5. Step 5: Solve for x
    x = 35,737.16/210.40
  6. Step 6: Final answer
    x = 169.85

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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.