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Finding the Fourth Proportional to 631.80, 871.80 and 352.05

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Solution

The fourth proportional to 631.80, 871.80 and 352.05 is: 485.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.80 : 871.80 = 352.05 : x
  2. Step 2: Convert to fraction form
    631.80/871.80 = 352.05/x
  3. Step 3: Cross multiply
    631.80x = 871.80 × 352.05
  4. Step 4: Simplify right side
    631.80x = 306,917.19
  5. Step 5: Solve for x
    x = 306,917.19/631.80
  6. Step 6: Final answer
    x = 485.78

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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.