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Finding the Fourth Proportional to 646.57, 890.76 and 630.78

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Solution

The fourth proportional to 646.57, 890.76 and 630.78 is: 869.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.57 : 890.76 = 630.78 : x
  2. Step 2: Convert to fraction form
    646.57/890.76 = 630.78/x
  3. Step 3: Cross multiply
    646.57x = 890.76 × 630.78
  4. Step 4: Simplify right side
    646.57x = 561,873.59
  5. Step 5: Solve for x
    x = 561,873.59/646.57
  6. Step 6: Final answer
    x = 869.01

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Half scale
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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.