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Finding the Fourth Proportional to 853.70, 1,279.65 and 487.70

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Solution

The fourth proportional to 853.70, 1,279.65 and 487.70 is: 731.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.70 : 1,279.65 = 487.70 : x
  2. Step 2: Convert to fraction form
    853.70/1,279.65 = 487.70/x
  3. Step 3: Cross multiply
    853.70x = 1,279.65 × 487.70
  4. Step 4: Simplify right side
    853.70x = 624,085.31
  5. Step 5: Solve for x
    x = 624,085.31/853.70
  6. Step 6: Final answer
    x = 731.04

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1.5x scale

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.