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Finding the Fourth Proportional to 812.45, 1,121.19 and 458.38

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Solution

The fourth proportional to 812.45, 1,121.19 and 458.38 is: 632.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.45 : 1,121.19 = 458.38 : x
  2. Step 2: Convert to fraction form
    812.45/1,121.19 = 458.38/x
  3. Step 3: Cross multiply
    812.45x = 1,121.19 × 458.38
  4. Step 4: Simplify right side
    812.45x = 513,923.17
  5. Step 5: Solve for x
    x = 513,923.17/812.45
  6. Step 6: Final answer
    x = 632.56

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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.