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Finding the Fourth Proportional to 210.39, 290.21 and 136.64

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Solution

The fourth proportional to 210.39, 290.21 and 136.64 is: 188.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.39 : 290.21 = 136.64 : x
  2. Step 2: Convert to fraction form
    210.39/290.21 = 136.64/x
  3. Step 3: Cross multiply
    210.39x = 290.21 × 136.64
  4. Step 4: Simplify right side
    210.39x = 39,652.16
  5. Step 5: Solve for x
    x = 39,652.16/210.39
  6. Step 6: Final answer
    x = 188.47

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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.