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Finding the Fourth Proportional to 290.28, 399.86 and 216.48

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Solution

The fourth proportional to 290.28, 399.86 and 216.48 is: 298.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.28 : 399.86 = 216.48 : x
  2. Step 2: Convert to fraction form
    290.28/399.86 = 216.48/x
  3. Step 3: Cross multiply
    290.28x = 399.86 × 216.48
  4. Step 4: Simplify right side
    290.28x = 86,561.69
  5. Step 5: Solve for x
    x = 86,561.69/290.28
  6. Step 6: Final answer
    x = 298.20

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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.