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Finding the Fourth Proportional to 631.80, 947.81 and 198.86

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Solution

The fourth proportional to 631.80, 947.81 and 198.86 is: 298.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.80 : 947.81 = 198.86 : x
  2. Step 2: Convert to fraction form
    631.80/947.81 = 198.86/x
  3. Step 3: Cross multiply
    631.80x = 947.81 × 198.86
  4. Step 4: Simplify right side
    631.80x = 188,477.25
  5. Step 5: Solve for x
    x = 188,477.25/631.80
  6. Step 6: Final answer
    x = 298.32

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.