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Finding the Fourth Proportional to 812.24, 1,118.94 and 646.40

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Solution

The fourth proportional to 812.24, 1,118.94 and 646.40 is: 890.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.24 : 1,118.94 = 646.40 : x
  2. Step 2: Convert to fraction form
    812.24/1,118.94 = 646.40/x
  3. Step 3: Cross multiply
    812.24x = 1,118.94 × 646.40
  4. Step 4: Simplify right side
    812.24x = 723,282.82
  5. Step 5: Solve for x
    x = 723,282.82/812.24
  6. Step 6: Final answer
    x = 890.48

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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.