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Finding the Fourth Proportional to 871.70, 1,305.40 and 611.07

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Solution

The fourth proportional to 871.70, 1,305.40 and 611.07 is: 915.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.70 : 1,305.40 = 611.07 : x
  2. Step 2: Convert to fraction form
    871.70/1,305.40 = 611.07/x
  3. Step 3: Cross multiply
    871.70x = 1,305.40 × 611.07
  4. Step 4: Simplify right side
    871.70x = 797,690.78
  5. Step 5: Solve for x
    x = 797,690.78/871.70
  6. Step 6: Final answer
    x = 915.10

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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.