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Finding the Fourth Proportional to 808.56, 1,115.44 and 631.20

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Solution

The fourth proportional to 808.56, 1,115.44 and 631.20 is: 870.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.56 : 1,115.44 = 631.20 : x
  2. Step 2: Convert to fraction form
    808.56/1,115.44 = 631.20/x
  3. Step 3: Cross multiply
    808.56x = 1,115.44 × 631.20
  4. Step 4: Simplify right side
    808.56x = 704,065.73
  5. Step 5: Solve for x
    x = 704,065.73/808.56
  6. Step 6: Final answer
    x = 870.76

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1.5x scale

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.