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Finding the Fourth Proportional to 678.90, 936.89 and 380.15

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Solution

The fourth proportional to 678.90, 936.89 and 380.15 is: 524.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.90 : 936.89 = 380.15 : x
  2. Step 2: Convert to fraction form
    678.90/936.89 = 380.15/x
  3. Step 3: Cross multiply
    678.90x = 936.89 × 380.15
  4. Step 4: Simplify right side
    678.90x = 356,152.15
  5. Step 5: Solve for x
    x = 356,152.15/678.90
  6. Step 6: Final answer
    x = 524.60

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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.