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Finding the Fourth Proportional to 678.76, 936.45 and 413.09

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Solution

The fourth proportional to 678.76, 936.45 and 413.09 is: 569.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.76 : 936.45 = 413.09 : x
  2. Step 2: Convert to fraction form
    678.76/936.45 = 413.09/x
  3. Step 3: Cross multiply
    678.76x = 936.45 × 413.09
  4. Step 4: Simplify right side
    678.76x = 386,838.13
  5. Step 5: Solve for x
    x = 386,838.13/678.76
  6. Step 6: Final answer
    x = 569.92

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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.