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Finding the Fourth Proportional to 421.17, 580.86 and 290.18

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Solution

The fourth proportional to 421.17, 580.86 and 290.18 is: 400.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.17 : 580.86 = 290.18 : x
  2. Step 2: Convert to fraction form
    421.17/580.86 = 290.18/x
  3. Step 3: Cross multiply
    421.17x = 580.86 × 290.18
  4. Step 4: Simplify right side
    421.17x = 168,551.05
  5. Step 5: Solve for x
    x = 168,551.05/421.17
  6. Step 6: Final answer
    x = 400.20

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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.