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Finding the Fourth Proportional to 631.51, 871.43 and 351.72

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Solution

The fourth proportional to 631.51, 871.43 and 351.72 is: 485.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.51 : 871.43 = 351.72 : x
  2. Step 2: Convert to fraction form
    631.51/871.43 = 351.72/x
  3. Step 3: Cross multiply
    631.51x = 871.43 × 351.72
  4. Step 4: Simplify right side
    631.51x = 306,498.06
  5. Step 5: Solve for x
    x = 306,498.06/631.51
  6. Step 6: Final answer
    x = 485.35

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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.