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Finding the Fourth Proportional to 678.90, 936.88 and 384.16

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Solution

The fourth proportional to 678.90, 936.88 and 384.16 is: 530.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.90 : 936.88 = 384.16 : x
  2. Step 2: Convert to fraction form
    678.90/936.88 = 384.16/x
  3. Step 3: Cross multiply
    678.90x = 936.88 × 384.16
  4. Step 4: Simplify right side
    678.90x = 359,908.52
  5. Step 5: Solve for x
    x = 359,908.52/678.90
  6. Step 6: Final answer
    x = 530.13

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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.