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Finding the Fourth Proportional to 677.70, 935.55 and 491.40

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Solution

The fourth proportional to 677.70, 935.55 and 491.40 is: 678.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    677.70 : 935.55 = 491.40 : x
  2. Step 2: Convert to fraction form
    677.70/935.55 = 491.40/x
  3. Step 3: Cross multiply
    677.70x = 935.55 × 491.40
  4. Step 4: Simplify right side
    677.70x = 459,729.27
  5. Step 5: Solve for x
    x = 459,729.27/677.70
  6. Step 6: Final answer
    x = 678.37

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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.