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Finding the Fourth Proportional to 678.80, 936.75 and 368.30

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Solution

The fourth proportional to 678.80, 936.75 and 368.30 is: 508.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.80 : 936.75 = 368.30 : x
  2. Step 2: Convert to fraction form
    678.80/936.75 = 368.30/x
  3. Step 3: Cross multiply
    678.80x = 936.75 × 368.30
  4. Step 4: Simplify right side
    678.80x = 345,000.34
  5. Step 5: Solve for x
    x = 345,000.34/678.80
  6. Step 6: Final answer
    x = 508.25

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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.