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Finding the Fourth Proportional to 812.04, 1,218.24 and 390.18

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Solution

The fourth proportional to 812.04, 1,218.24 and 390.18 is: 585.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.04 : 1,218.24 = 390.18 : x
  2. Step 2: Convert to fraction form
    812.04/1,218.24 = 390.18/x
  3. Step 3: Cross multiply
    812.04x = 1,218.24 × 390.18
  4. Step 4: Simplify right side
    812.04x = 475,332.88
  5. Step 5: Solve for x
    x = 475,332.88/812.04
  6. Step 6: Final answer
    x = 585.36

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Double scale
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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.