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Finding the Fourth Proportional to 1,380.38, 2,070.62 and 649.44

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Solution

The fourth proportional to 1,380.38, 2,070.62 and 649.44 is: 974.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380.38 : 2,070.62 = 649.44 : x
  2. Step 2: Convert to fraction form
    1,380.38/2,070.62 = 649.44/x
  3. Step 3: Cross multiply
    1,380.38x = 2,070.62 × 649.44
  4. Step 4: Simplify right side
    1,380.38x = 1,344,740.21
  5. Step 5: Solve for x
    x = 1,344,740.21/1,380.38
  6. Step 6: Final answer
    x = 974.18

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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.