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Finding the Fourth Proportional to 290.40, 400.80 and 207.44

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Solution

The fourth proportional to 290.40, 400.80 and 207.44 is: 286.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.40 : 400.80 = 207.44 : x
  2. Step 2: Convert to fraction form
    290.40/400.80 = 207.44/x
  3. Step 3: Cross multiply
    290.40x = 400.80 × 207.44
  4. Step 4: Simplify right side
    290.40x = 83,141.95
  5. Step 5: Solve for x
    x = 83,141.95/290.40
  6. Step 6: Final answer
    x = 286.30

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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.