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Finding the Fourth Proportional to 210.30, 290.22 and 121.79

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Solution

The fourth proportional to 210.30, 290.22 and 121.79 is: 168.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.30 : 290.22 = 121.79 : x
  2. Step 2: Convert to fraction form
    210.30/290.22 = 121.79/x
  3. Step 3: Cross multiply
    210.30x = 290.22 × 121.79
  4. Step 4: Simplify right side
    210.30x = 35,345.89
  5. Step 5: Solve for x
    x = 35,345.89/210.30
  6. Step 6: Final answer
    x = 168.08

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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.