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Finding the Fourth Proportional to 811.44, 1,119.24 and 645.36

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Solution

The fourth proportional to 811.44, 1,119.24 and 645.36 is: 890.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.44 : 1,119.24 = 645.36 : x
  2. Step 2: Convert to fraction form
    811.44/1,119.24 = 645.36/x
  3. Step 3: Cross multiply
    811.44x = 1,119.24 × 645.36
  4. Step 4: Simplify right side
    811.44x = 722,312.73
  5. Step 5: Solve for x
    x = 722,312.73/811.44
  6. Step 6: Final answer
    x = 890.16

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Double scale
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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.