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Finding the Fourth Proportional to 1,981.02, 2,972.20 and 664.90

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Solution

The fourth proportional to 1,981.02, 2,972.20 and 664.90 is: 997.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,981.02 : 2,972.20 = 664.90 : x
  2. Step 2: Convert to fraction form
    1,981.02/2,972.20 = 664.90/x
  3. Step 3: Cross multiply
    1,981.02x = 2,972.20 × 664.90
  4. Step 4: Simplify right side
    1,981.02x = 1,976,215.78
  5. Step 5: Solve for x
    x = 1,976,215.78/1,981.02
  6. Step 6: Final answer
    x = 997.57

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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.