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Finding the Fourth Proportional to 678.96, 936.78 and 430.40

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Solution

The fourth proportional to 678.96, 936.78 and 430.40 is: 593.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.96 : 936.78 = 430.40 : x
  2. Step 2: Convert to fraction form
    678.96/936.78 = 430.40/x
  3. Step 3: Cross multiply
    678.96x = 936.78 × 430.40
  4. Step 4: Simplify right side
    678.96x = 403,185.43
  5. Step 5: Solve for x
    x = 403,185.43/678.96
  6. Step 6: Final answer
    x = 593.83

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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.