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Finding the Fourth Proportional to 678.78, 936.75 and 416.76

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Solution

The fourth proportional to 678.78, 936.75 and 416.76 is: 575.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.78 : 936.75 = 416.76 : x
  2. Step 2: Convert to fraction form
    678.78/936.75 = 416.76/x
  3. Step 3: Cross multiply
    678.78x = 936.75 × 416.76
  4. Step 4: Simplify right side
    678.78x = 390,399.93
  5. Step 5: Solve for x
    x = 390,399.93/678.78
  6. Step 6: Final answer
    x = 575.15

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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.