Home / 1,279.40-1,919.16-457.65

Finding the Fourth Proportional to 1,279.40, 1,919.16 and 457.65

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Solution

The fourth proportional to 1,279.40, 1,919.16 and 457.65 is: 686.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.40 : 1,919.16 = 457.65 : x
  2. Step 2: Convert to fraction form
    1,279.40/1,919.16 = 457.65/x
  3. Step 3: Cross multiply
    1,279.40x = 1,919.16 × 457.65
  4. Step 4: Simplify right side
    1,279.40x = 878,303.57
  5. Step 5: Solve for x
    x = 878,303.57/1,279.40
  6. Step 6: Final answer
    x = 686.50

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Half scale
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Double scale
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Similar ratio
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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.