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Finding the Fourth Proportional to 290.55, 400.78 and 211.77

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Solution

The fourth proportional to 290.55, 400.78 and 211.77 is: 292.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.55 : 400.78 = 211.77 : x
  2. Step 2: Convert to fraction form
    290.55/400.78 = 211.77/x
  3. Step 3: Cross multiply
    290.55x = 400.78 × 211.77
  4. Step 4: Simplify right side
    290.55x = 84,873.18
  5. Step 5: Solve for x
    x = 84,873.18/290.55
  6. Step 6: Final answer
    x = 292.11

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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.