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Finding the Fourth Proportional to 853.56, 1,178.30 and 643.82

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Solution

The fourth proportional to 853.56, 1,178.30 and 643.82 is: 888.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.56 : 1,178.30 = 643.82 : x
  2. Step 2: Convert to fraction form
    853.56/1,178.30 = 643.82/x
  3. Step 3: Cross multiply
    853.56x = 1,178.30 × 643.82
  4. Step 4: Simplify right side
    853.56x = 758,608.82
  5. Step 5: Solve for x
    x = 758,608.82/853.56
  6. Step 6: Final answer
    x = 888.76

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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.