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Finding the Fourth Proportional to 290.64, 401.21 and 220.71

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Solution

The fourth proportional to 290.64, 401.21 and 220.71 is: 304.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.64 : 401.21 = 220.71 : x
  2. Step 2: Convert to fraction form
    290.64/401.21 = 220.71/x
  3. Step 3: Cross multiply
    290.64x = 401.21 × 220.71
  4. Step 4: Simplify right side
    290.64x = 88,549.96
  5. Step 5: Solve for x
    x = 88,549.96/290.64
  6. Step 6: Final answer
    x = 304.67

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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.