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Finding the Fourth Proportional to 678.75, 936.69 and 445.89

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Solution

The fourth proportional to 678.75, 936.69 and 445.89 is: 615.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.75 : 936.69 = 445.89 : x
  2. Step 2: Convert to fraction form
    678.75/936.69 = 445.89/x
  3. Step 3: Cross multiply
    678.75x = 936.69 × 445.89
  4. Step 4: Simplify right side
    678.75x = 417,660.70
  5. Step 5: Solve for x
    x = 417,660.70/678.75
  6. Step 6: Final answer
    x = 615.34

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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.