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Finding the Fourth Proportional to 631.14, 870.72 and 398.34

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Solution

The fourth proportional to 631.14, 870.72 and 398.34 is: 549.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.14 : 870.72 = 398.34 : x
  2. Step 2: Convert to fraction form
    631.14/870.72 = 398.34/x
  3. Step 3: Cross multiply
    631.14x = 870.72 × 398.34
  4. Step 4: Simplify right side
    631.14x = 346,842.60
  5. Step 5: Solve for x
    x = 346,842.60/631.14
  6. Step 6: Final answer
    x = 549.55

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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.