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Finding the Fourth Proportional to 290.64, 398.99 and 287.91

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Solution

The fourth proportional to 290.64, 398.99 and 287.91 is: 395.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.64 : 398.99 = 287.91 : x
  2. Step 2: Convert to fraction form
    290.64/398.99 = 287.91/x
  3. Step 3: Cross multiply
    290.64x = 398.99 × 287.91
  4. Step 4: Simplify right side
    290.64x = 114,872.31
  5. Step 5: Solve for x
    x = 114,872.31/290.64
  6. Step 6: Final answer
    x = 395.23

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.