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Finding the Fourth Proportional to 918.20, 1,377.36 and 398.30

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Solution

The fourth proportional to 918.20, 1,377.36 and 398.30 is: 597.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    918.20 : 1,377.36 = 398.30 : x
  2. Step 2: Convert to fraction form
    918.20/1,377.36 = 398.30/x
  3. Step 3: Cross multiply
    918.20x = 1,377.36 × 398.30
  4. Step 4: Simplify right side
    918.20x = 548,602.49
  5. Step 5: Solve for x
    x = 548,602.49/918.20
  6. Step 6: Final answer
    x = 597.48

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.