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Finding the Fourth Proportional to 812.34, 1,121.58 and 646.16

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Solution

The fourth proportional to 812.34, 1,121.58 and 646.16 is: 892.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.34 : 1,121.58 = 646.16 : x
  2. Step 2: Convert to fraction form
    812.34/1,121.58 = 646.16/x
  3. Step 3: Cross multiply
    812.34x = 1,121.58 × 646.16
  4. Step 4: Simplify right side
    812.34x = 724,714.52
  5. Step 5: Solve for x
    x = 724,714.52/812.34
  6. Step 6: Final answer
    x = 892.13

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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.