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Finding the Fourth Proportional to 811.56, 1,119.78 and 480.09

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Solution

The fourth proportional to 811.56, 1,119.78 and 480.09 is: 662.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.56 : 1,119.78 = 480.09 : x
  2. Step 2: Convert to fraction form
    811.56/1,119.78 = 480.09/x
  3. Step 3: Cross multiply
    811.56x = 1,119.78 × 480.09
  4. Step 4: Simplify right side
    811.56x = 537,595.18
  5. Step 5: Solve for x
    x = 537,595.18/811.56
  6. Step 6: Final answer
    x = 662.42

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.