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Finding the Fourth Proportional to 631.09, 870.97 and 421.19

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Solution

The fourth proportional to 631.09, 870.97 and 421.19 is: 581.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.09 : 870.97 = 421.19 : x
  2. Step 2: Convert to fraction form
    631.09/870.97 = 421.19/x
  3. Step 3: Cross multiply
    631.09x = 870.97 × 421.19
  4. Step 4: Simplify right side
    631.09x = 366,843.85
  5. Step 5: Solve for x
    x = 366,843.85/631.09
  6. Step 6: Final answer
    x = 581.29

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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.