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Finding the Fourth Proportional to 290.19, 399.89 and 207.15

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Solution

The fourth proportional to 290.19, 399.89 and 207.15 is: 285.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.19 : 399.89 = 207.15 : x
  2. Step 2: Convert to fraction form
    290.19/399.89 = 207.15/x
  3. Step 3: Cross multiply
    290.19x = 399.89 × 207.15
  4. Step 4: Simplify right side
    290.19x = 82,837.21
  5. Step 5: Solve for x
    x = 82,837.21/290.19
  6. Step 6: Final answer
    x = 285.46

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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.