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Finding the Fourth Proportional to 1,992.91, 2,987.56 and 1,288.21

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Solution

The fourth proportional to 1,992.91, 2,987.56 and 1,288.21 is: 1,931.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,992.91 : 2,987.56 = 1,288.21 : x
  2. Step 2: Convert to fraction form
    1,992.91/2,987.56 = 1,288.21/x
  3. Step 3: Cross multiply
    1,992.91x = 2,987.56 × 1,288.21
  4. Step 4: Simplify right side
    1,992.91x = 3,848,604.67
  5. Step 5: Solve for x
    x = 3,848,604.67/1,992.91
  6. Step 6: Final answer
    x = 1,931.15

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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.