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Finding the Fourth Proportional to 678.23, 935.58 and 491.39

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Solution

The fourth proportional to 678.23, 935.58 and 491.39 is: 677.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.23 : 935.58 = 491.39 : x
  2. Step 2: Convert to fraction form
    678.23/935.58 = 491.39/x
  3. Step 3: Cross multiply
    678.23x = 935.58 × 491.39
  4. Step 4: Simplify right side
    678.23x = 459,737.70
  5. Step 5: Solve for x
    x = 459,737.70/678.23
  6. Step 6: Final answer
    x = 677.85

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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.