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Finding the Fourth Proportional to 1,279.86, 1,919.69 and 499.71

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Solution

The fourth proportional to 1,279.86, 1,919.69 and 499.71 is: 749.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.86 : 1,919.69 = 499.71 : x
  2. Step 2: Convert to fraction form
    1,279.86/1,919.69 = 499.71/x
  3. Step 3: Cross multiply
    1,279.86x = 1,919.69 × 499.71
  4. Step 4: Simplify right side
    1,279.86x = 959,289.54
  5. Step 5: Solve for x
    x = 959,289.54/1,279.86
  6. Step 6: Final answer
    x = 749.53

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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.