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Finding the Fourth Proportional to 812.68, 1,121.32 and 480.85

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Solution

The fourth proportional to 812.68, 1,121.32 and 480.85 is: 663.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.68 : 1,121.32 = 480.85 : x
  2. Step 2: Convert to fraction form
    812.68/1,121.32 = 480.85/x
  3. Step 3: Cross multiply
    812.68x = 1,121.32 × 480.85
  4. Step 4: Simplify right side
    812.68x = 539,186.72
  5. Step 5: Solve for x
    x = 539,186.72/812.68
  6. Step 6: Final answer
    x = 663.47

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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.