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Finding the Fourth Proportional to 906.20, 1,249.80 and 644.36

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Solution

The fourth proportional to 906.20, 1,249.80 and 644.36 is: 888.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    906.20 : 1,249.80 = 644.36 : x
  2. Step 2: Convert to fraction form
    906.20/1,249.80 = 644.36/x
  3. Step 3: Cross multiply
    906.20x = 1,249.80 × 644.36
  4. Step 4: Simplify right side
    906.20x = 805,321.13
  5. Step 5: Solve for x
    x = 805,321.13/906.20
  6. Step 6: Final answer
    x = 888.68

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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.