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Finding the Fourth Proportional to 1,005.88, 1,379.06 and 987.39

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Solution

The fourth proportional to 1,005.88, 1,379.06 and 987.39 is: 1,353.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,005.88 : 1,379.06 = 987.39 : x
  2. Step 2: Convert to fraction form
    1,005.88/1,379.06 = 987.39/x
  3. Step 3: Cross multiply
    1,005.88x = 1,379.06 × 987.39
  4. Step 4: Simplify right side
    1,005.88x = 1,361,670.05
  5. Step 5: Solve for x
    x = 1,361,670.05/1,005.88
  6. Step 6: Final answer
    x = 1,353.71

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.