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Finding the Fourth Proportional to 678.85, 936.81 and 384.19

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Solution

The fourth proportional to 678.85, 936.81 and 384.19 is: 530.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.85 : 936.81 = 384.19 : x
  2. Step 2: Convert to fraction form
    678.85/936.81 = 384.19/x
  3. Step 3: Cross multiply
    678.85x = 936.81 × 384.19
  4. Step 4: Simplify right side
    678.85x = 359,910.69
  5. Step 5: Solve for x
    x = 359,910.69/678.85
  6. Step 6: Final answer
    x = 530.18

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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.