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Finding the Fourth Proportional to 678.89, 936.87 and 368.39

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Solution

The fourth proportional to 678.89, 936.87 and 368.39 is: 508.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.89 : 936.87 = 368.39 : x
  2. Step 2: Convert to fraction form
    678.89/936.87 = 368.39/x
  3. Step 3: Cross multiply
    678.89x = 936.87 × 368.39
  4. Step 4: Simplify right side
    678.89x = 345,133.54
  5. Step 5: Solve for x
    x = 345,133.54/678.89
  6. Step 6: Final answer
    x = 508.38

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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.