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Finding the Fourth Proportional to 421.66, 581.88 and 290.80

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Solution

The fourth proportional to 421.66, 581.88 and 290.80 is: 401.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.66 : 581.88 = 290.80 : x
  2. Step 2: Convert to fraction form
    421.66/581.88 = 290.80/x
  3. Step 3: Cross multiply
    421.66x = 581.88 × 290.80
  4. Step 4: Simplify right side
    421.66x = 169,210.70
  5. Step 5: Solve for x
    x = 169,210.70/421.66
  6. Step 6: Final answer
    x = 401.30

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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.